Enhanced detection using special road coloring

ABSTRACT

Disclosed herein are methods and systems for detecting dynamic objects using road painted patterns perceptible in infrared spectral range, comprising receiving images captured in one or more infrared spectral ranges depicting a road segment painted with background patterns which are highly imperceptible in visible light spectrum while highly visible in one or more infrared spectral ranges, analyzing the images to detecting one or more dynamic objects located in front of the background patterns. The light reflected by the one or more dynamic objects in the one or more infrared spectral ranges deviating from the light reflected by the one or more background pattern and computing a location of the one or more identified objects. Further disclosed are methods and systems for calibration of systems and/or sensors based on reference markings which are highly imperceptible in visible light spectrum while highly visible in the infrared spectral range(s).

RELATED APPLICATIONS

This application is a Continuation-in-Part (CIP) of U.S. patentapplication Ser. No. 17/191,793 filed on Mar. 4, 2021.

This application is also a Continuation-in-Part (CIP) of U.S. PatentApplication No. 17/327,973 filed on May 24, 2021, which is aContinuation-in-Part (CIP) of U.S. patent application Ser. No.17/313,161 filed on May 6, 2021, which is a Continuation-in-Part (CIP)of U.S. patent application Ser. No. 17/191,793 filed on Mar. 4, 2021.

The contents of the above applications are all incorporated by referenceas if fully set forth herein in their entirety.

FIELD AND BACKGROUND OF THE INVENTION

The present invention, in some embodiments thereof, relates to paintingroad markings to support object detection, and, more specifically, butnot exclusively, to painting road markings visible in the infraredspectrum while imperceptible in the human visible light spectrum tosupport object detection.

Road markings have evolved over the years since the introduction ofmotorized vehicles and the development of roads infrastructures to hostthese vehicles in order to assist drivers to grasp and understand theirmotorized environment and take actions accordingly.

Recent times have witnessed major advancement, evolution and in fact arevolution in the development and deployment of automated systems, forexample, traffic monitor and/or control systems, road safety systemsand/or the like deployed to monitor transportation traffic whethervehicles or pedestrians in attempt to increase traffic flow efficiency,increase road safety, enforce traffic regulations and/or the like.

Road markings may be deployed to increase the capabilities and/orperformance of such traffic monitoring systems, for example, accuracy,reliability, robustness and/or the like.

SUMMARY OF THE INVENTION

According to a first aspect of the present invention there is provided amethod of detecting dynamic objects using road painted patternsperceptible in infrared spectral range, comprising using one or moreprocessors for:

-   -   Receiving one or more infrared images depicting, in one or more        infrared spectral ranges, one or more surfaces of one or more        road segments painted with one or more background patterns using        one or more paint materials characterized by: (1) reflecting        light in visible light spectral range deviating less than a        first value from the light reflected by the one or more        surfaces, and (2) reflecting light in the one or more infrared        spectral ranges deviating more than a second value from the        light reflected by the one or more surfaces.    -   Analyzing the one or more infrared images to detecting one or        more dynamic objects located in front of one or more of the        background patterns. The light reflected by the one or more        dynamic objects in the one or more infrared spectral ranges        deviating from the light reflected by the one or more background        pattern.    -   Computing a location of the one or more identified objects.

According to a second aspect of the present invention there is provideda system for detecting dynamic objects using road painted patternsperceptible in infrared spectral range, comprising one or moreprocessors configured to execute a code. The code comprising:

-   -   Code instruction to receive one or more infrared images        depicting, in one or more infrared spectral ranges, one or more        surfaces of one or more road segments painted with one or more        background patterns using one or more paint materials        characterized by: (1) reflecting light in visible light spectral        range deviating less than a first value from the light reflected        by the one or more surfaces, and (2) reflecting light in the one        or more infrared spectral ranges deviating more than a second        value from the light reflected by the one or more surfaces.    -   Code instruction to analyze the one or more infrared images to        detecting one or more dynamic objects located in front of one or        more of the background patterns. The light reflected by the one        or more dynamic objects in the one or more infrared spectral        ranges deviating from the light reflected by the one or more        background pattern.    -   Code instruction to compute a location of the one or more        identified objects.

According to a third aspect of the present invention there is provided amethod of computing instruction for painting background patternsperceptible in infrared spectral range to support detection of dynamicobjects, comprising using one or more processors for:

-   -   Computing instructions for painting one or more background        patterns on one or more surfaces of one or more road segments        using one or more paint materials characterized by: (1)        reflecting light in a visible light spectral range deviating        less than a first value from the visible light spectral range        reflected by the surface, and (2) reflecting light in one or        more infrared spectral ranges deviating more than a second value        from the light reflected by the surface.    -   Outputting the painting instructions for applying the one or        more paint materials on the one or more surfaces according to        the instructions such that the one or more background patterns        are perceptible in the one or more infrared spectral ranges        while significantly imperceptible in the visible spectral range.        Wherein one or more one or more dynamic objects reflecting light        in the one or more infrared spectral ranges deviating from the        light reflected by the one or more background patterns is        detectable when located in front of the one or more background        patterns.

According to a fourth aspect of the present invention there is provideda system for computing instruction for painting background patternsperceptible in infrared spectral range to support detection of dynamicobjects, comprising one or more processor configured to execute a code,the code comprising:

-   -   Code instruction to compute instructions for painting one or        more background patterns on one or more surfaces of one or more        road segments using one or more paint materials characterized        by: (1) reflecting light in a visible light spectral range        deviating less than a first value from the visible light        spectral range reflected by the surface, and (2) reflecting        light in one or more infrared spectral ranges deviating more        than a second value from the light reflected by the surface.    -   Code instruction to output the painting instructions for        applying the one or more paint materials on the one or more        surfaces according to the instructions such that the one or more        background patterns are perceptible in the one or more infrared        spectral ranges while significantly imperceptible in the visible        spectral range.        Wherein one or more one or more dynamic objects reflecting light        in the one or more infrared spectral ranges deviating from the        light reflected by the one or more background patterns is        detectable when located in front of the one or more background        patterns.

According to a fifth aspect of the present invention there is provided abackground pattern painted on one or more surfaces of one or more roadsegments using one or more paint materials characterized by: (1)reflecting light in visible light spectral range deviating less than afirst value from the light reflected by the one or more surfaces, and(2) reflecting light in one or more infrared spectral ranges deviatingmore than a second value from the light reflected by the one or moresurfaces. Wherein one or more dynamic objects reflecting light in theone or more infrared spectral ranges deviating from the light reflectedby the background pattern are detectable when located in front of thebackground pattern.

According to a sixth aspect of the present invention there is provided amethod of calibrating imaging sensors deployed to monitor roads trafficaccording to infrared visible reference markings, comprising using oneor more processors for:

-   -   Receiving one or more one or more infrared images captured by        one or more imaging sensors depicting, in one or more infrared        spectral ranges, one or more surfaces of one or more road        segments painted with one or more reference markings using one        or more paint materials characterized by: (1) reflecting light        in visible light spectral range deviating less than a first        value from the light reflected by the one or more surfaces,        and (2) reflecting light in one or more infrared spectral ranges        deviating more than a second value from the light reflected by        the one or more surfaces.    -   Analyzing the one or more infrared images to determine a        position of the one or more reference markings.    -   Calibrating the one or more imaging sensors according to the        computed position of the one or more reference markings.

According to a seventh aspect of the present invention there is provideda system for calibrating imaging sensors deployed to monitor roadstraffic according to infrared visible reference markings, comprising oneor more processor configured to execute a code. The code comprising:

-   -   Code instruction to receive one or more one or more infrared        images captured by one or more imaging sensors depicting, in one        or more infrared spectral ranges, one or more surfaces of one or        more road segments painted with one or more reference markings        using one or more paint materials characterized by: (1)        reflecting light in visible light spectral range deviating less        than a first value from the light reflected by the one or more        surfaces, and (2) reflecting light in one or more infrared        spectral ranges deviating more than a second value from the        light reflected by the one or more surfaces.    -   Code instruction to analyze the one or more infrared images to        determine a position of the one or more reference markings.    -   Code instruction to calibrate the one or more imaging sensors        according to the computed position of the one or more reference        markings.

According to an eighth aspect of the present invention there is provideda reference markings painted on one or more surfaces of one or more roadsegments using one or more paint materials characterized by: (1)reflecting light in visible light spectral range deviating less than afirst value from the light reflected by the one or more surfaces, and(2) reflecting light in one or more infrared spectral ranges deviatingmore than a second value from the light reflected by the one or moresurfaces. Wherein the reference markings perceptible in the infraredspectral range while significantly imperceptible in the visible spectralrange are detectable in the infrared spectral range for calibrating oneor more imaging sensors deployed to monitor transportation traffic inthe one or more road segments.

In a further implementation form of the first, second, third, fourth,fifth, sixth, seventh and/or eighth aspects, the first value equals 20%and the second value equals 25%.

In a further implementation form of the first, second, third, fourth,fifth, sixth, seventh and/or eighth aspects, the one or more infraredspectral ranges are members of a group consisting of: near infrared(NIR) having a wavelength in a range of 750-1400 nanometer, and shortwave infrared (SWIR) having a wavelength in a range of 1400-3000nanometer.

In a further implementation form of the second value of the one or morepaint materials characterizes the one or more paint materials totransfer more than a fourth value of light in the one or more infraredspectral ranges thus exposing the one or more background patternspainted beneath the one or more paint materials. The fourth value equals85%.

In a further implementation form of the first, second, third, fourthand/or fifth aspects, the one or more dynamic objects are members of agroup consisting of: a vehicle and a pedestrian.

In an optional implementation form of the first, second, third, fourthand/or fifth aspects, a plurality of background patterns are painted onthe one or more surfaces suing a plurality of paint materials such asthe one or more paint materials which are further characterized byreflecting light in the one or more infrared spectral ranges deviatingfrom each other by more than a third value, the third value equals 25%.

In a further implementation form of the first, second, third, fourthand/or fifth aspects, the one or more images are analyzed to compute oneor more attributes of the one or more identified objects. The one ormore attributes are members of a group consisting of: a size, a length,a width, a height, a speed, an acceleration and a movement direction.

In a further implementation form of the first, second, third, fourthand/or fifth aspects, the one or more surfaces on which the one or morebackground patterns are painted comprise one or more members of a groupconsisting of: a road surface, a sidewalk surface and a transportationinfrastructure object surface.

In a further implementation form of the first, second, third, fourthand/or fifth aspects, the one or more background patterns are appliedover one or more of the surfaces which are already painted with one ormore paint materials perceptible in the visible light range.

In a further implementation form of the sixth, seventh and/or eighthaspects, the one or more reference markings further comprising anidentifier of the one or more road segments.

In a further implementation form of the sixth, seventh and/or eighthaspects, the one or more reference markings are applied over one or moreof the surfaces which is already painted with one or more paintmaterials perceptible in the visible light range.

Other systems, methods, features, and advantages of the presentdisclosure will be or become apparent to one with skill in the art uponexamination of the following drawings and detailed description. It isintended that all such additional systems, methods, features, andadvantages be included within this description, be within the scope ofthe present disclosure, and be protected by the accompanying claims.

Unless otherwise defined, all technical and/or scientific terms usedherein have the same meaning as commonly understood by one of ordinaryskill in the art to which the invention pertains. Although methods andmaterials similar or equivalent to those described herein can be used inthe practice or testing of embodiments of the invention, exemplarymethods and/or materials are described below. In case of conflict, thepatent specification, including definitions, will control. In addition,the materials, methods, and examples are illustrative only and are notintended to be necessarily limiting.

Implementation of the method and/or system of embodiments of theinvention can involve performing or completing selected tasksautomatically. Moreover, according to actual instrumentation andequipment of embodiments of the method and/or system of the invention,several selected tasks could be implemented by hardware, by software orby firmware or by a combination thereof using an operating system.

For example, hardware for performing selected tasks according toembodiments of the invention could be implemented as a chip or acircuit. As software, selected tasks according to embodiments of theinvention could be implemented as a plurality of software instructionsbeing executed by a computer using any suitable operating system. In anexemplary embodiment of the invention, one or more tasks according toexemplary embodiments of methods and/or systems as described herein areperformed by a data processor, such as a computing platform forexecuting a plurality of instructions. Optionally, the data processorincludes a volatile memory for storing instructions and/or data and/or anon-volatile storage, for example, a magnetic hard-disk and/or removablemedia, for storing instructions and/or data. Optionally, a networkconnection is provided as well. A display and/or a user input devicesuch as a keyboard or mouse are optionally provided as well.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Some embodiments of the invention are herein described, by way ofexample only, with reference to the accompanying drawings. With specificreference now to the drawings in detail, it is stressed that theparticulars are shown by way of example and for purposes of illustrativediscussion of embodiments of the invention. In this regard, thedescription taken with the drawings makes apparent to those skilled inthe art how embodiments of the invention may be practiced.

In the drawings:

FIG. 1 is a flowchart of an exemplary process of computing instructionsfor painting driving assistance marking using paint material(s) visiblein the infrared spectrum while imperceptible in the visible lightspectrum, according to some embodiments of the present invention;

FIG. 2 is a schematic illustration of an exemplary system for computinginstructions for painting driving assistance marking using paintmaterial(s) visible in the infrared spectrum while imperceptible in thevisible light spectrum, according to some embodiments of the presentinvention;

FIG. 3A and FIG. 3B are exemplary road segments comprising elementssuitable for painting driving assistance marking painted using paintmaterial(s) visible in the infrared spectrum while imperceptible in thevisible light spectrum, according to some embodiments of the presentinvention;

FIG. 4 presents color blends of an exemplary infrared reflective paintmaterial(s) visible in the infrared spectrum while imperceptible in thevisible light spectrum used for painting imperceptible drivingassistance markings, according to some embodiments of the presentinvention;

FIG. 5 presents images of a road section painted with an exemplary paintmaterial(s) visible in the infrared spectrum while imperceptible in thevisible light spectrum used for painting driving assistance markings,according to some embodiments of the present invention;

FIG. 6A and FIG. 6B illustrate exemplary road markings painted usingpaint material(s) visible in the infrared spectrum while imperceptiblein the visible light spectrum used for painting additional roadmarkings, according to some embodiments of the present invention;

FIG. 7A and FIG. 7B present exemplary background patterns painted in anexemplary road segment using paint material(s) visible in the infraredspectrum while imperceptible in the visible light spectrum, according tosome embodiments of the present invention;

FIG. 8 is a flowchart of an exemplary process of detecting dynamicobjects crossing background patterns painted using infrared reflectivepaint material(s), according to some embodiments of the presentinvention;

FIG. 9 is a schematic illustration of an exemplary system for detectingdynamic objects crossing background patterns painted using infraredreflective paint material(s), according to some embodiments of thepresent invention;

FIG. 10 is an exemplary process of calibration based on road referencemarkings painted using paint material(s) visible in the infraredspectrum while imperceptible in the visible light spectrum, according tosome embodiments of the present invention; and

FIG. 11A and FIG. 11B present exemplary reference markings painted in anexemplary intersection using paint material(s) visible in the infraredspectrum while imperceptible in the visible light spectrum, according tosome embodiments of the present invention.

DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION

The present invention, in some embodiments thereof, relates to paintingroad markings to support object detection, and, more specifically, butnot exclusively, to painting road markings visible in the infraredspectrum while imperceptible in the human visible light spectrum tosupport object detection.

According to some embodiments of the present invention, there areprovided methods, systems and computer program products for computinginstructions for painting driving assistance markings which are highlyvisible in the infrared light spectrum while highly imperceptible in thevisible light spectrum. In particular, the driving assistance markingsmay significantly blend with their background in the visible light rangemaking them significantly imperceptible by the human eye and thusinvisible to human drivers.

The term imperceptible as used here in through the document definesobjects, markings, printing and/or the like, in particular drivingassistance markings which may not be perceived by the human eye sincethey reflect light in a spectral range which is out of the visible lightspectral range (400-700 nanometer).

These driving assistance markings which are highly imperceptible to thehuman drivers are therefore directed to support automated vehicularsystems, for example, an Advanced Driving Assistance System (ADAS), avehicular monitoring system, a vehicular alert system, a vehicularcontrol system and/or the like installed in one or more vehicles whichmay be manual, partially autonomous and/or fully autonomous.

Specifically, the driving assistance markings are directed for suchautomated vehicular systems which are capable of operating in theinfrared light spectrum, in particulate, systems which are coupled,integrated and/or connected to one or more imaging sensors, for example,a camera, an infrared camera, a thermal mapping camera, a LightDetection and Ranging (LiDAR) sensor and/or the like configured tocapture images of the vehicle's surroundings in the infrared spectrum,for example, Near Infrared (NIR), Short Wave Infrared (SWIR) and/or thelike.

The driving assistance markings generated for one or more road segmentsmay express informative directions and/or operation assistanceinformation. For example, one or more informative driving assistancemarkings may indicate presence and optionally distance to one or moreobjects in the respective road segment and/or of one or more subsequentroad segments, for example, a pedestrian crossing, a railroad crossing,a traffic light, a junction, a maximal allowed speed and/or the like. Inanother example, one or more operation assistance driving assistancemarkings may include markers, pointers, guides, keys and/or the likewhich may be identified and used by the automated vehicular systems tomaneuver the vehicles, for example, break, accelerate, decelerate, turnand/or the like.

The driving assistance markings generated for the road segment(s) may bepainted (applied) on one or more elements of the respective roadsegment, for example, one or more surface sections of the road segment,one or more colored marks painted on the road segment (e.g., laneseparator lines, arrows, stop lines, pedestrian crossings, etc.) and/orone or more infrastructure objects located in proximity to the roadsegment (e.g., next to, on, above, etc.), for example, pavement surfacesand/or edges, traffic poles, traffic lights, structure walls and/or thelike.

In order to ensure that the driving assistance markings are highlyvisible in the infrared spectrum while substantially imperceptible inthe visible light spectrum and hence imperceptible to the human drivers,the driving assistance markings may be painted to significantly blendwith their background in the visible light range while be significantlydistinguishable from their background in the infrared spectral range. Tothis end the driving assistance markings may be painted using one ormore infrared reflective paint materials which are characterized by twomain characteristics.

First, the infrared reflective paint materials selected for painting thedriving assistance markings must not significantly deviate from thecolor of the surface of the element(s) selected for painting the drivingassistance markings. This means that the visible light reflected by theselected infrared reflective paint material(s) must not deviate by morethan a certain value (e.g. 10%, 15%, 20%, etc.) from the visible lightspectrum reflected by the surface of the selected element(s).

In addition, the infrared reflective paint materials selected forpainting the driving assistance markings must be significantlydistinguishable from the surface of the selected element(s) in theinfrared spectrum. This means that the infrared spectral range reflectedby the selected infrared reflective paint material(s) must deviate bymore than a certain value (e.g. 25%, 30%, 35%, etc.) from the infraredspectral range reflected by the surface of the selected element(s).

While for brevity the paint material(s) selected for painting thedriving assistance markings are designated infrared reflective paintmaterials, obviously, the deviation of the infrared reflective paintmaterial(s) compared to their background may be to both directions. Thismeans that the paint material(s) used for painting the drivingassistance markings may be more infrared reflective or more absorptivecompared to the surrounding background of the markings, i.e., thesurface of the selected element(s) on which the markings are painted.When the paint material(s) is more infrared reflective, the drivingassistance markings will reflect more infrared light compared to theirsurrounding background and will be thus visible in the infrared spectrumrange. When the paint material(s) is more infrared absorptive, i.e.,less infrared reflective, the driving assistance markings will reflectless infrared light compared to their surrounding background and will betherefore also visible in the infrared spectrum range.

Optionally, the driving assistance markings may be painted in proximity,specifically closely around one or more visible road markings of one ormore of the road segments, for example, lane separator markings, roadside border line markings, pedestrian crossings, painted directionsymbols, painted text and/or the like.

Painting the driving assistance markings using the infrared reflectivepaint materials and computing instructions thereof may present majoradvantages and benefits compared to currently existing methods andsystems for applying road markings in roads.

First, while the human perception and recognition of road markings maybe limited, the automated vehicular systems may have a significantlylarger capacity for detecting and recognizing large volumes of roadmarkings. These automated vehicular systems may therefore benefit fromextensive additional driving assistance markings which may express anddeliver increased volumes of information relating to the road segmentsand/or may provide increased, improved and/or enhanced assistance withvehicle control actions. However, in case the extensive road markingsare visible as may be done using existing methods for applying roadmarkings, the road markings may cause a major clutter which maysignificantly overload human drivers' perception which may lead to humanmistakes potentially resulting in dangerous scenarios and increased riskon the road. In contrast, painting (applying) the additional drivingassistance markings using the infrared reflective paint material(s) suchthat the driving assistance markings are imperceptible to the humandrivers while visible to the infrared capable automated vehicularsystems may overcome the clutter limitation while highly enhancing theassistance and support to the automated vehicular systems.

Moreover, existing (legacy) automated vehicular systems which similarlyto the human drivers rely on visible light road markings may be alsohighly degraded in case the additional driving assistance markings arevisible in the visible light spectrum. Such existing (legacy) automatedvehicular systems may be limited in their ability to distinguish betweenextensive road markings painted in close proximity and all visible inthe same light spectrum. On the other hand, the existing automatedvehicular systems may be oblivious and unaware of the additional drivingassistance markings which are only visible in the infrared spectrum thusprevent the overload and degradation in the operation of these legacysystems.

Furthermore, applying (painting) driving assistance markings in twodifferent light spectrums, namely the visible light and the infraredspectrums may allow for increased detection and/or redundancy since theroad markings, even identical markings, may be captured by imagingsensors in two distinct domains. The performance, for example, accuracy,robustness, reliability and/or certainty of the detection of theautomated vehicular systems may be highly increased when relying onimagery data captured in both the visible light and infrared spectrums,typically by different imaging sensors. Moreover, visible light markingsmay be significantly undetectable under certain circumstances, forexample, low illumination, large distance and/or the like. Relying onthe infrared visible road markings may therefore enable the automatedvehicular systems to operate with high performance in such scenarios.

In addition, distracting objects which are typically visible in thevisible light spectrum, for example, spilled paint, trash and/or anyother object that may be located on the road segment or in its closevicinity may be erroneously detected and/or interpreted by the automatedvehicular systems as valid road markings which are visible in thevisible light spectrum. Such degraded detection may result in potentialerroneous detection that may lead to dangerous, critical and even fatalsituation. Painting the driving assistance markings to be visible in theinfrared spectrum, on the other hand, may significantly increase thedetection performance, specifically robustness, reliability and/orreliability since infrared reflectance and/or absorption may be rare innaturally occurring objects such as the distracting objects thus makingthese naturally occurring objects significantly imperceptible in theinfrared spectrum which may reduce and even completely prevent erroneousdetection of these object as valid road markings.

Also, adding visible road markings (visible in the visible lightspectrum) may be subject to regulation since they may affect the roadconditions and perception as described herein before. Adding theinfrared visible driving assistance markings on the other hand, may notbe subject to any such regulation which may be highly costly, timelyand/or demanding, since the additional road markings are imperceptibleand practically invisible to the human drivers and/or to the existingautomated vehicular systems configured to operate in the visible lightspectrum.

Finally, painting the infrared visible driving assistance markings inproximity to visible road markings may significantly increase accuracy,robustness, reliability and/or certainty of the automated vehicularsystems to detect of the driving assistance markings. Moreover, theautomated vehicular systems may ignore and/or avoid erroneousinterpretation of potential infrared reflective materials and/orsections of the road segment arbitrarily present in one or more of theroad segments.

According to some embodiments of the present invention, there areprovided methods, systems and computer program products for computinginstructions for painting, in one or more road segments, road markingswhich are highly perceptible (visible) in one or more infrared spectralranges, for example, NIR, SWIR and/or the like while highlyimperceptible (invisible) in the visible light spectral range.

In particular, the road markings comprising one or more backgroundpatterns may be painted on one or more surfaces of the road, sidewalkand/or practically any other transportation infrastructure object (e.g.signs, poles, barrier rails, bridges, etc.) are painted and marked tosupport detection of one or more dynamic objects, for example, a vehicle(e.g. car, motorcycle, bicycle, truck, bus, train, etc.), a pedestrianand/or the like passing in front of the background pattern(s).

For brevity, the term reflection is used herein after for bothreflection and absorption since light reflection and absorption arepractically two sides of the same phenomena where high lightreflectiveness may be regarded as low light absorption and vice versalow light reflectiveness may be regarded as high light absorption.Similarly, the term infrared reflective material may designate bothmaterials which are highly reflective and/or highly absorptive in termsof reflected infrared light

The background patterns may be painted on the road surface in one ormore shapes, sizes and/or the like using one or more paint materials(colors) characterized by reflecting visible light deviating by lessthan a first value, for example, 10%, 15%, 20% and/or the like from thevisible light reflected by the surface on which they are painted.However, the light reflected by the background patterns in one or moreof the infrared spectral ranges, for example, NIR, SWIR and/or the likemay deviate by more than a second value, for example, 20%, 25%, 30%and/or the like from the infrared light reflected by the surface.

Moreover, a plurality of background patterns may be painted on thesurface using a plurality of paint materials which differ from eachother in their infrared reflectiveness (or absorption) by more than athird value, for example, 20%, 25%, 30% and/or the like. As such, evenif one or more of the dynamic objects reflect infrared light which doesnot significantly deviate from the infrared light reflected by thebackground pattern(s) painted using a first paint material, the infraredlight reflected by the dynamic object(s) may significantly deviate fromthe infrared light reflected by the background pattern(s) painted usinga second paint material which is different in its infrared reflectioncharacteristics from the first paint material.

Optionally, one or more of the paint materials may be characterized byreflecting visible light deviating by less than the first value from thevisible light reflected by the selected surface(s) while transferring atleast some and typically most of the infrared light in one or more ofthe infrared spectral ranges (e.g. NIR, SWIR, etc.). As such, one ormore of the background patterns may be painted on the selected surfaceswhich may be further painted with the at least partially infraredtransparent paint material(s). As such while blending with the surfacein the visible light spectrum, the at least partially infraredtransparent paint material(s) may become at least partially transparentin the infrared spectral range(s) thus exposing the backgroundpattern(s) painted beneath them.

One or more object detection systems, in particular object detectionsystems deployed to detect transportation traffic, for example, vehicletraffic, pedestrians traffic and/or the like may be configured toidentify one or more of the dynamic objects in particular when passingin front of one or more of the background patterns painted on one ormore of the surfaces (e.g. road surface, sidewalk surface, etc.) of oneor more road segments which are highly imperceptible in the visiblelight spectral range while highly visible in the infrared spectralrange(s), for example, NIR, SWIR and/or the like.

The object detection system(s) may receive sensory data, specifically,imagery data (i.e. images) of the road surfaces, sidewalk surfacesand/or other surfaces of one or more of the road segments painted withone or more background patterns from one or more imaging sensorsdeployed to monitor the road segment(s).

The object detection system(s) may analyze the captured images toidentify one or more of the dynamic objects passing in front of thebackgrounds pattern(s) which may be highly detectable due to theirdifferent infrared light reflection characteristics compared to thebackgrounds pattern(s) painted with the highly reflective paintmaterial(s). The object detection system(s) may analyze the capturedimages using one or more methods, techniques and/or algorithms as knownin the art, for example, computer vision, image processing,classification functions and/or models (classifiers) and/or the like.

The object detection system(s) may further analyze the captured imagesto track the identified dynamic object(s) in consecutive images and maycompute one or more attributes of the identified dynamic object(s)accordingly, for example, a dimension (e.g. size, length, width, height,etc.), a speed, an acceleration, a movement direction (vector) and/orthe like.

According to some embodiments of the present invention, there areprovided methods, systems and computer program products for computinginstructions for painting, in one or more road segments, referencemarkings which are highly perceptible (visible) in one or more infraredspectral ranges, for example, NIR, SWIR and/or the like while highlyimperceptible (invisible) in the visible light spectral range.

Optionally, one or more of the reference markings may be painted beneathone or more of the at least partially infrared transparent paintmaterials which may become transparent in the infrared spectral range(s)thus exposing the reference markings painted beneath them.

The reference markings may be painted on one or more surfaces of theroad segment(s) to support calibration of imaging sensors deployed tocapture imagery data of the road segments. The reference markings may befurther painted to support traffic detection by one or moretransportation traffic monitoring systems, for example, a red lightcrossing detection system, a lane crossing detection system, an accidentanalysis system and/or the like.

The reference markings may be painted according to one or morepredefined patterns, symbol, marks, dimensions, locations and/or thelike which may be used to calibrate the imaging sensor(s). For example,one or more reference markings may be painted on the road surface of acretin intersection at one or more predefined locations, for example, acenter of the intersection, at each entry point to the intersection,across the intersection and/or the like. In such case, one or moreimaging sensors deployed to monitor the certain intersection which areconfigured to operate in the infrared spectral range(s) may captureimages depicting the reference marking(s). Based on the location,position, dimensions and/or the like of the reference markings detectedby analyzing the captured images, the imaging sensor(s) may beautomatically calibrated and adapted to their exact location andpositioning in the certain intersection.

Moreover, one or more reference markings may be further painted to markone or more elements and/or objects in one or more of the road segments,for example, a lane separation line, a stop line, a pedestrian crossing,an intersection entry point, an intersection exit point and/or the like.One or more of the traffic monitoring systems may use these referencemarkings to improve their detection and/or analysis functionality. Forexample, a certain traffic monitoring system configured to detectvehicles entering an intersection on red light may analyze imagesdepicting the intersection and passing vehicles. Based on analysis ofthe image(s) captured in the inferred spectral range(s), the trafficmonitoring system may detect one or more reference markings designating,for example, one or more entry points to the intersection and/or one ormore exit point from the intersection. Based on the detected referencemarkings, the traffic monitoring system may accurately identify vehiclescrossing the entry point(s) and/or exit point(s) including accuratetiming of the crossing.

Painting the background patterns and the reference markings,collectively designated additional road markings, using the infraredreflective and/or absorptive paint material(s) to support objectdetection may present major advantages and benefits compared tocurrently existing methods and systems for object detection.

First, detection performance, for example, accuracy, reliability and/orthe like of the dynamic objects against the background patterns paintedusing the infrared reflective paint materials may be significantlyimproved compared to the detection performance of the dynamic objectsover surfaces colored in visible light colors as may be done by theexisting object detection methods. This is because the color of thedynamic objects may be very similar in the visible light spectral rangeto that of the background surfaces. In addition, visible light colorsand respective paint materials may be highly sensitive to lightingand/or illumination conditions as well as to light reflections by mirrorlike surfaces. The infrared reflective paint materials on the other handmay provide a significantly improved contrast to the dynamic objects inthe infrared spectral range(s) thus significantly improving thedetection performance of the dynamic objects. Operating in the infraredspectral range is also significantly more robust compared to the visiblelight range with respect to lighting, illumination, reflections and/orthe like which are highly common in the visible light range. Theseadvantages are further increased when the object detection is applied todetect far away dynamic objects which may therefore appear very small inthe images since the limitations described herein before (colorsimilarity with the background and/or susceptibility to lighting andreflections) may be significantly increased when the objects to bedetected occupy just a small portion of the image.

Moreover, painting the reference markings may enable automatedcalibration of the imaging sensors deployed to monitor the road segmentsthus eliminating the need for specifically calibrating each imagingsensor, typically manually, according to its specific deploymentlocation and conditions (e.g., height, view angle, etc.). In addition,using the reference markings designating various elements of the roadsegments (e.g. lanes, stop lines, road edges, intersection entry/exitpoints, etc.) may significantly improve the performance of the trafficmonitoring system(s) which may more easily detect the dynamic objects(e.g., vehicles, pedestrians, etc.) relative to the road segmentsinfrastructure. The reference markings may be further used todynamically calibrate the imaging sensor(s) over time as their positionand/or orientation may shift over time due to, for example, wind,vibrations and/or the like.

Furthermore, as described herein before, painting the additional roadmarkings (background patterns and/or the reference markings) usinginfrared reflective paint material(s) imperceptible in the visible lightrange may make the additional road markings highly usable by theautomated traffic monitoring systems while avoiding excessive visualclutter potentially overloading the human driver perception as mayhappen should the additional road markings were visible in the visiblelight spectral range.

In addition, as they are imperceptible (invisible) in the visible lightspectral range, the additional road markings may not be subject toexcessive and strict regulation as is required for road markings visiblein the visible light spectral range.

Also, capturing images in the infrared spectrum to support detection ofthe background patterns may be done using standard equipment, forexample, infrared sensors, LiDAR sensors and/or the like which arehighly available and common in a plurality of already deployed trafficmonitoring systems and therefore impose no additional costs, complexityand/or effort to facilitate capturing of the infrared images.

Before explaining at least one embodiment of the invention in detail, itis to be understood that the invention is not necessarily limited in itsapplication to the details of construction and the arrangement of thecomponents and/or methods set forth in the following description and/orillustrated in the drawings and/or the Examples. The invention iscapable of other embodiments or of being practiced or carried out invarious ways.

As will be appreciated by one skilled in the art, aspects of the presentinvention may be embodied as a system, method or computer programproduct. Accordingly, aspects of the present invention may take the formof an entirely hardware embodiment, an entirely software embodiment(including firmware, resident software, micro-code, etc.) or anembodiment combining software and hardware aspects that may allgenerally be referred to herein as a “circuit,” “module” or “system.”Furthermore, aspects of the present invention may take the form of acomputer program product embodied in one or more computer readablemedium(s) having computer readable program code embodied thereon.

Any combination of one or more computer readable medium(s) may beutilized. The computer readable storage medium can be a tangible devicethat can retain and store instructions for use by an instructionexecution device. The computer readable storage medium may be, forexample, but is not limited to, an electronic storage device, a magneticstorage device, an optical storage device, an electromagnetic storagedevice, a semiconductor storage device, or any suitable combination ofthe foregoing. A non-exhaustive list of more specific examples of thecomputer readable storage medium includes the following: a portablecomputer diskette, a hard disk, a random access memory (RAM), aread-only memory (ROM), an erasable programmable read-only memory (EPROMor Flash memory), a static random access memory (SRAM), a portablecompact disc read-only memory (CD-ROM), a digital versatile disk (DVD),a memory stick, a floppy disk, a mechanically encoded device such aspunch-cards or raised structures in a groove having instructionsrecorded thereon, and any suitable combination of the foregoing. Acomputer readable storage medium, as used herein, is not to be construedas being transitory signals per se, such as radio waves or other freelypropagating electromagnetic waves, electromagnetic waves propagatingthrough a waveguide or other transmission media (e.g., light pulsespassing through a fiber-optic cable), or electrical signals transmittedthrough a wire.

Computer program code comprising computer readable program instructionsembodied on a computer readable medium may be transmitted using anyappropriate medium, including but not limited to wireless, wire line,optical fiber cable, RF, etc., or any suitable combination of theforegoing.

The computer readable program instructions described herein can bedownloaded to respective computing/processing devices from a computerreadable storage medium or to an external computer or external storagedevice via a network, for example, the Internet, a local area network, awide area network and/or a wireless network. The network may comprisecopper transmission cables, optical transmission fibers, wirelesstransmission, routers, firewalls, switches, gateway computers and/oredge servers. A network adapter card or network interface in eachcomputing/processing device receives computer readable programinstructions from the network and forwards the computer readable programinstructions for storage in a computer readable storage medium withinthe respective computing/processing device.

The computer readable program instructions for carrying out operationsof the present invention may be written in any combination of one ormore programming languages, such as, for example, assemblerinstructions, instruction- set-architecture (ISA) instructions, machineinstructions, machine dependent instructions, microcode, firmwareinstructions, state-setting data, or either source code or object codewritten in any combination of one or more programming languages,including an object oriented programming language such as Smalltalk, C++or the like, and conventional procedural programming languages, such asthe “C” programming language or similar programming languages.

The computer readable program instructions may execute entirely on theuser's computer, partly on the user's computer, as a stand-alonesoftware package, partly on the user's computer and partly on a remotecomputer or entirely on the remote computer or server. In the latterscenario, the remote computer may be connected to the user's computerthrough any type of network, including a local area network (LAN) or awide area network (WAN), or the connection may be made to an externalcomputer (for example, through the Internet using an Internet ServiceProvider). In some embodiments, electronic circuitry including, forexample, programmable logic circuitry, field-programmable gate arrays(FPGA), or programmable logic arrays (PLA) may execute the computerreadable program instructions by utilizing state information of thecomputer readable program instructions to personalize the electroniccircuitry, in order to perform aspects of the present invention.

Aspects of the present invention are described herein with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems), and computer program products according to embodiments of theinvention. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer readable program instructions.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof instructions, which comprises one or more executable instructions forimplementing the specified logical function(s). In some alternativeimplementations, the functions noted in the block may occur out of theorder noted in the figures. For example, two blocks shown in successionmay, in fact, be executed substantially concurrently, or the blocks maysometimes be executed in the reverse order, depending upon thefunctionality involved. It will also be noted that each block of theblock diagrams and/or flowchart illustration, and combinations of blocksin the block diagrams and/or flowchart illustration, can be implementedby special purpose hardware-based systems that perform the specifiedfunctions or acts or carry out combinations of special purpose hardwareand computer instructions.

Referring now to the drawings, FIG. 1 is a flowchart of an exemplaryprocess of computing instructions for painting driving assistancemarking using paint material(s) visible in the infrared spectrum whileimperceptible in the visible light spectrum, according to someembodiments of the present invention.

An exemplary process 100 may be executed for computing instructions forpainting driving assistance markings to support one or more automatedvehicular systems, for example, an ADAS system, a vehicular monitoringsystem, a vehicular alert system, a vehicular control system and/or thelike installed in one or more vehicles which may be fully manual withone or more alert systems, partially autonomous and/or fully autonomous.

Specifically, the driving assistance markings are painted on one or moreelements of one or more road segments such that the driving assistancemarkings are highly visible in the infrared spectral range (e.g. NIR,SWIR) while significantly imperceptible and thus practically invisiblein the visible light range. Imperceptible in the visible light spectrum,the driving assistance markings are therefore highly imperceptible byhuman drivers as well as to automated vehicular systems which are basedin visible light imaging.

Automated vehicular systems which are capable of analyzing infraredspectrum images on the other hand may identify the driving assistancemarkings which may express informative and/or operation assistanceinformation.

The imperceptible driving assistance markings may therefore provideadditional driving assistance information beyond the traditional roadmarkings which may be used by the infrared enabled vehicular systemswhile preventing visual clutter which may overload perception of thedrivers and/or of the visual light spectrum based systems.

Reference is also made to FIG. 2, which is a schematic illustration ofan exemplary system for computing instructions for painting drivingassistance marking using paint material(s) visible in the infraredspectrum while imperceptible in the visible light spectrum, according tosome embodiments of the present invention.

An exemplary road markings generation system 200, for example, acomputer, a server, a processing node, a cluster of computing nodesand/or the like may be configured to execute a process such as theprocess 100 for computing instructions for painting driving assistancemarkings which are visible in in the infrared spectrum wileimperceptible in the visible light spectrum.

The road markings generation system 200 may include an Input/Output(I/O) interface 210, a processor(s) 212 for executing the process 100and storage 214 for storing code (program store) and/or data.

The I/O interface 210 may include one or more wired and/or wirelessnetwork interfaces for connecting to one or more networks, for example,a Local Area Network (LAN), a Wide Area Network (WAN), a MetropolitanArea Network (MAN), a cellular network, the internet and/or the like.The I/O interface 210 may further include one or more wired and/orwireless interconnection interfaces, for example, a Universal Serial Bus(USB) interface, a serial port, a Controller Area Network (CAN) businterface, a Radio Frequency (RF) interface and/or the like.

Via the I/O interface 210, the road markings generation system 200 mayobtain, for example, fetch, receive, acquire and/or the like one or moreimages of one or more road segments. For example, the road markingsgeneration system 200 may connect to one or more of the networks,through the network interface(s) available in the I/O interface 210, tocommunicate with one or more networked resources storing one or more ofthe images. In another example, the road markings generation system 200may access one or more attachable devices attached to interconnectioninterface(s) available in the I/O interface 210, for example, a USBstorage device storing, capturing and/or recording one or more of theimages.

The processor(s) 212, homogenous or heterogeneous, may include one ormore processing nodes arranged for parallel processing, as clustersand/or as one or more multi core processor(s). The storage 214 mayinclude one or more non-transitory persistent storage devices, forexample, a hard drive, a Flash array and/or the like. The storage 214may also include one or more volatile devices, for example, a RandomAccess Memory (RAM) component and/or the like. The storage 214 mayfurther include one or more network storage resources, for example, astorage server, a Network Attached Storage (NAS), a network drive,and/or the like accessible via one or more networks through the I/Ointerface 210.

The processor(s) 212 may execute one or more software modules such as,for example, a process, a script, an application, an agent, a utility, atool, an Operating System (OS) and/or the like each comprising aplurality of program instructions stored in a non-transitory medium(program store) such as the storage 214 and executed by one or moreprocessors such as the processor(s) 212. The processor(s) 212 mayoptionally, integrate, utilize and/or facilitate one or more hardwareelements (modules) integrated and/or utilized in the road markingsgeneration system 200, for example, a circuit, a component, anIntegrated Circuit (IC), an Application Specific Integrated Circuit(ASIC), a Field Programmable Gate Array (FPGA), a Digital SignalsProcessor (DSP), a Graphic Processing Unit (GPU), an ArtificialIntelligence (AI) accelerator and/or the like.

The processor(s) 212 may therefore execute one or more functionalmodules implemented using one or more software modules, one or more ofthe hardware modules and/or combination thereof. For example, theprocessor(s) 212 may execute a road markings engine 220 functionalmodule for executing the process 100 to generate driving assistancemarkings and compute instructions for painting the driving assistancemarkings using one or more infrared visible paint materials such thatthe driving assistance markings are highly visible in the infraredspectrum while significantly imperceptible and potentially completelyinvisible in the visible light spectrum.

The road markings engine 220 may further output the paintinginstructions computed for painting the driving assistance markings usingone or more of the infrared visible paint materials.

Optionally, the road markings engine 220 may receive one or more drivingassistance information rules which may be applicable for one or more ofthe road segments.

Optionally, the road markings generation system 200, specifically theroad markings engine 220 are provided and/or utilized by one or morecloud computing services, for example, Infrastructure as a Service(IaaS), Platform as a Service (PaaS), Software as a Service (SaaS)and/or the like provided by one or more cloud infrastructures, platformsand/or services such as, for example, Amazon Web Service (AWS), GoogleCloud, Microsoft Azure and/or the like.

For brevity, the process 100 executed by road markings engine 220 isdescribed for computing instructions for painting driving assistancemarkings in a single road segment. This, however, should not beconstrued as limiting since the process 100 may be expanded forcomputing painting instructions for driving assistance markings in aplurality of road segments.

As shown at 102, the process 100 starts with the road markings engine220 receiving one or more images of a road segment.

The image(s) may be captured at ground level, from an elevated location(e.g. building, poles, posts, etc.), from the air (e.g. by a drone, anaircraft, etc.), from space (satellite) and/or the like such that theroad segment may be depicted from one or more elevation points and/orangles.

The road markings engine 220 may receive the image(s) from one or moresources. For example, one or more images may be retrieved from one ormore data stores, for example, a database, a storage server, a storageservice and/or the like which stores images depicting one or more roadsegments. In another example, one or more of the images may be receivedfrom one or more mapping services, for example, goggle earth, googlestreet view and/or the like.

As shown at 104, the road markings engine 220 may generate drivingassistance markings for the road segment, in particular the roadmarkings engine 220 may generate the driving assistance markings basedon analysis of the image(s) of the road segment.

The computed driving assistance markings are directed to support one ormore automated vehicular systems of one or more vehicles riding throughthe road segment. Such automated vehicular systems may include, forexample, one or more ADAS systems as known in the art configured toassist vehicle drivers. In another example, the automated vehicularsystems may include one or more monitoring systems configured to monitorthe environment of the vehicle and report, alert and/or otherwiseindicate of one or more potential hazards, risks and/or conditionsdetected in the road segment. In another example, the automatedvehicular systems may include one or more automatic vehicular controlsystems of one or more at least partially autonomous vehicles configuredto control operation of the vehicle (e.g. break, maneuver, accelerate,etc.) based on one or more conditions, potential hazards and/or the likedetected in the road segment.

Specifically, the driving assistance markings generated by the roadmarkings engine 220 are intended to be added (painted) to the roadsegment such that the driving assistance markings are visible in theinfrared spectrum, for example, NIR, SWIR and/or the like whilesignificantly imperceptible in the visible light spectrum. The drivingassistance markings are therefore directed to support automatedvehicular systems which are capable of operating in the infraredspectrum, in particular, automated vehicular systems which integrate,employ, connect and/or communicate with one or more imaging sensors, forexample, a camera, infrared camera, a thermal camera, a Light Detectionand Ranging (LiDAR) sensor and/or the like adapted to operate in theinfrared spectral range, for example, NIR, SWIR and/or the like.

The driving assistance markings generated by the road markings engine220 may express driving information relating to the road segment. Thedriving information expressed by the driving assistance markings mayinclude descriptive information relating to one or more transportationinfrastructure objects located in the road segment as identified byanalyzing the image(s), for example, a junction, a traffic light, atraffic sign, a pedestrian crossing, a bridge, a tunnel, a freewayand/or the like. For example, assuming there is a 4-way junction in theroad segment with traffic lights and pedestrian crossings in all fourdirections. In such case, the road markings engine 220 may generatedriving assistance markings which report the presence of the 4-wayjunction in the road segment. In particular, the road markings engine220 may generate driving assistance markings which indicate the distanceto the 4-way junction in the road segment, for example, the 4-wayjunction is 50 meters ahead, 30 meters ahead, 10 meters ahead and/or thelike. In another example, assuming there is a sharp left curve in theroad segment. In such case, the road markings engine 220 may generatedriving assistance markings which report the presence of the sharp leftcurve in the road segment and may further configure the drivingassistance markings to indicate the distance to the sharp left curve.

The driving assistance markings may further express driving informationdirected to assist one or more of the automatic vehicular controlsystems of at least one vehicle to conduct at least one controloperation of the at least one vehicle. For example, assuming there is asharp right curve in the road segment. In such case, the road markingsengine 220 may generate orientation points road markings extending froma certain distance before the beginning of the right curve through thecurve and until the curve end which may be used by the automaticvehicular control system(s) to accurately maneuver the respectivevehicle(s) in the sharp curve. In another example, assuming there is atraffic light in the road segment. In such case, the road markingsengine 220 may mark a stop line road markings right before the trafficlight where vehicles must come to a complete stop. The stop line roadmarkings may be used by as orientation points by the automatic vehicularcontrol system(s) to identify the exact stop location and may controlthe vehicle(s) accordingly, apply breaks to fully stop the vehicle(s).

The driving assistance markings generated by the road markings engine220 may express driving information similar to driving informationexpressed by visible road markings in the road segment which are visiblein the visible light spectrum. This may of course be essential forsupporting automatic vehicular control systems connected to imagingsensors which operated only in the infrared spectrum and hence monitorthe surrounding of the vehicles in the infrared spectrum. However,duplicating the driving assistance markings may also serve forredundancy and/or to improve detection of the road markings in both thevisible light spectrum and in the infrared spectrum for automaticvehicular control systems capable of monitoring the surrounding of thevehicle(s) in both the visible light and infrared spectrums.

However, the driving assistance markings generated by the road markingsengine 220 may include and/or express additional driving informationwhich is not expressed and/or available from the visible road markings.Traditionally, the road markings are directed for human drivers and arethus presented (painted, drawn, placed, etc.) to be visible in thevisible light spectrum. The amount of information expressed by the roadmarkings which may be efficiently consumed and comprehended by humandrivers may be limited. The automatic vehicular control system(s) on theother hand may be able to acquire and process much larger volumes ofdriving information expressed by road markings. However, addingadditional driving information visible to the human drivers may lead tomajor clutter which may overload perception and/or confuse the humandrivers and may be therefore inefficient and potentially dangerous.Expressing the additional driving information via the infrared visibledriving assistance markings may therefore overcome this limitation sincethe driving assistance markings are substantially and potentiallycompletely imperceptible to the human drivers while visible to theinfrared capable automatic vehicular control system(s) which may use theadditional driving information.

The driving assistance markings may include human readable markingswhich may be identified and recognized by automatic vehicular controlsystem(s) designed, configured and/or adapted to rely on road markingsdirected for human drivers. However, the driving assistance markings mayfurther include markings, signs, symbols, expressions and/or the likewhich are directed for machines and may thus not be comprehended byhumans, for example, coded data (e.g. barcode, QR code, etc.), machinelanguage symbolic data and/or the like. While incomprehensible byhumans, automatic vehicular control system(s) configured accordingly maybe of course able to identify, decipher and use such machine directeddriving assistance markings.

Optionally, the road markings engine 220 may generate driving assistancemarkings which are applied in the (current) road segment but may relateto one or more transportation infrastructure objects located in one ormore subsequent road segments located after the (current) road segment.For example, assuming there is a mountain tunnel one mile ahead of the(current) road segment. Further assuming that one or more automaticvehicular control system(s) include radar sensors highly suitable forlow and/or no illumination imaging. In such case, the automaticvehicular control system(s) may bring the radar sensors online and/ortest them prior to entry into the tunnel.

Optionally, the road markings engine 220 may compute one or more of thedriving assistance markings according to one or more of the drivingassistance information rules which may be received from one or moresources.

The driving assistance information rules may include one or more generalrules applicable for a plurality of road segments sharing one or moreparameters and/or attributes. For example, a certain general drivingassistance information rule may indicate that each road segment whichcomprises a pedestrian crossing should include driving assistancemarkings at one or more locations preceding the pedestrian crossing(e.g. 100 meters, 50 meters, 15 meters, etc.) to inform of the upcomingpedestrian crossing. In another example, a certain general drivingassistance information rule may indicate that driving assistancemarkings should be included in each road segment to indicate a maximumspeed allowed in the respective road segment. In another example, acertain general driving assistance information rule may indicate thatcurve orientation points driving assistance markings should be includedin each road segment comprising one or more curves exceeding a certaincurve angle, for example, 10 degrees, 15 degrees, 25 degrees and/or thelike.

However, the driving assistance information rules may also include oneor more specific rules applicable for one or more specific roadsegments. For example, a certain specific driving assistance informationrule may indicate that special driving assistance markings should beapplied in the road segment in case the specific road segment includes atraffic circle immediately followed by another traffic circle withinless than a certain distance, for example, 50 meters, 80 meters and/orthe like. The special driving assistance markings which may be appliedbefore the first circle may express the multiple traffic circles whichmay require some special attention by tone or more of the automaticvehicular control systems.

As shown at 106, the road markings engine 220 may analyze the image(s)of the road segment to identify and select one or more elements of theroad segment which are suitable for applying (painting) the drivingassistance markings generated for the road segment.

The elements on which the driving assistance markings may be painted nayinclude, for example, one or more surface sections of the road segment,one or more colored marks painted on the road segment, one or moreinfrastructure objects located in proximity to the road segment (e.g.,next to, on, above, etc.) and/or the like. The colored marks painted onthe road segment may include visible road markings such as, for example,lane separator markings, road side border line markings, pedestriancrossings, painted direction symbols (e.g., arrows, stop lines, etc.),painted text (e.g. stop, slow, etc.) and/or the like. The infrastructureobjects may include, for example, pavement edges, traffic poles, trafficlights, structures wall and/or the like.

Reference is now made to FIG. 3A and FIG. 3B, which are exemplary roadsegments comprising elements suitable for painting driving assistancemarkings painted using paint material(s) visible in the infraredspectrum while imperceptible in the visible light spectrum, according tosome embodiments of the present invention.

An exemplary road segment 300A may comprise a plurality of elementswhich may be identified by a road markings engine such as the roadmarkings engine 220 as suitable for applying (painting) the drivingassistance markings generated for the road segment. For example, theroad markings engine 220 analyzing one or more images of the roadsegment 300A may identify one or more surface sections 302 of the roadsegment 300A which may be suitable for painting the driving assistancemarkings, for example, surface section 302A, 302B, 302C and/or 302D. Inanother example, the road markings engine 220 analyzing one or moreimages of the road segment 300A may identify one or more visible roadmarkings 304 painted in the road segment 300A which may be suitable forpainting the driving assistance markings, for example, an arrow marking304A, a pedestrian crossing marking 304B a lane separator line 304C andand/or a road border line 302D. In another example, the road markingsengine 220 analyzing one or more images of the road segment 300A mayidentify one or more infrastructure object 306 of the road segment 300Awhich may be suitable for painting the driving assistance markings, forexample, a traffic light pole 306A, a lighting pole 306B, a wall of abridge 306C and/or a sidewalk surface 306D.

An exemplary road segment 300B may also comprise a plurality of elementswhich may be identified by the road markings engine 220 as suitable forapplying (painting) the driving assistance markings generated for theroad segment. For example, the road markings engine 220 analyzing one ormore images of the road segment 300B may identify one or more visibleroad markings 304 painted in the road segment 300B which may be suitablefor painting the driving assistance markings, for example, a road borderline 302D. In another example, the road markings engine 220 analyzingone or more images of the road segment 300B may identify one or moreinfrastructure object 306 of the road segment 30BA which may be suitablefor painting the driving assistance markings, for example, a sidebarrier rail 306E.

The road markings engine 220 may therefore analyze the image(s) toidentify one or more elements in the road segments which may be suitablefor painting the generated driving assistance markings. In particular,the road markings engine 220 may select one or more of the identifiedelements according to the generated driving assistance markings.

For example, assuming the road segment comprises a pedestrian crossingand the road markings engine 220 generated driving assistance markingsaccordingly to indicate the presence of the pedestrian crossing andfurther indicate a distance to the pedestrian crossing. In such case,the road markings engine 220 may select one or more visible roadmarkings, for example, lane separator lines for applying (painting) thedriving assistance markings. In particular, the road markings engine 220may select one or more lane separator lines and/or line sections whichare located at the distance from the pedestrian crossing as indicated bythe respective driving assistance markings. For example, assuming threedriving assistance markings are generated to indicate the pedestriancrossing is 10, 30 and 50 meters ahead. In such case, the road markingsengine 220 may select three lane separator lines and/or line sectionslocated at 10, 30 and 50 meters before the pedestrian crossing on whichthe respective driving assistance markings may be painted.

In another example, assuming the road segment comprises a junction andthe road markings engine 220 generated driving assistance markingsaccordingly to indicate the presence of the junction. In such case, theroad markings engine 220 may select one or more road surfaces of theroad segment for applying (painting) the driving assistance markingsindicating the upcoming junction. For example, the road markings engine220 may select a plurality of consecutive surface sections of the roadsegment for painting decrementing distance values to the junction.

In another example, assuming the road segment comprises a railroadintersection and the road markings engine 220 generated drivingassistance markings accordingly to indicate the presence of the railroadintersection. In such case, the road markings engine 220 may select oneor more infrastructure objects, for example, a slowdown traffic signpole for applying (painting) the driving assistance markings indicatingthe upcoming railroad intersection.

Moreover, the road markings engine 220 may adjust one or more of thedriving assistance markings according to the selected element(s) onwhich the driving assistance markings generated for the road segment areto be painted. For example, assuming the road markings engine 220selects a traffic pole located 45 meters before an intersection forpainting driving assistance markings indicative of the intersection, theroad markings engine 220 may adjust and/or generate the drivingassistance markings which are to be applied on the traffic pole toindicate that the intersection is 45 meters ahead. In another example,assuming the road markings engine 220 selects a series of lighting polesdistributed along a sharp curve for applying (paining) orientationpoints driving assistance markings to assist the automatic vehicularcontrol systems to maneuver the vehicles along the curve. In such case,the road markings engine 220 may adjust the size of the orientationpoints to fit the lighting poles while ensuring high visibility of theorientation points.

As shown at 108, the road markings engine 220 may analyze one or more ofthe surfaces of one or more of the selected element(s) on which thedriving assistance markings generated for the road segment are to bepainted. In particular, the road markings engine 220 may analyze theimage(s) of the road segment to identify a color of the surface(s) ofthe selected element(s) and more specifically to identify the spectralrange of visible light reflected by the surface(s) of the selectedelement(s).

For example, assuming the road markings engine 220 selects a certainroad surface section of the road segment for applying the drivingassistance markings, the road markings engine 220 may identify that theroad surface section is a black asphalt surface which accordinglyreflects visible light in a spectral range corresponding to black color.In another example, assuming the road markings engine 220 selects acertain road marking of the road segment for applying the drivingassistance markings, the road markings engine 220 may identify that theroad marking is painted white and thus reflects visible light in aspectral range corresponding to white color. In another example,assuming the road markings engine 220 selects a certain traffic pole ofthe road segment for applying the driving assistance markings, the roadmarkings engine 220 may identify that the traffic pole is painted and/orcoated with gray paint and thus reflects visible light in a spectralrange corresponding to gray color.

As shown at 110, the road markings engine 220 may select one or morepaint materials for applying (painting) the driving assistance markingsgenerated for the road segment on the selected element(s) of the roadsegment.

Specifically, the road markings engine 220 may select infraredreflective paint material(s) which reflect infrared light in one or moreinfrared spectral ranges, for example, NIR (750-1400 nm), SWIR(1400-3000 nm) and/or the like and are further characterized by two maincharacteristics.

First, each of the selected paint materials may reflect light in thevisible light spectral range which is substantially similar to thevisible light spectral range of the surface(s) of the selected object(s)on which the driving assistance markings are to be applied.Specifically, each paint material selected for painting the drivingassistance markings may deviate by less than a first value from thevisible light spectral range reflected by the respective surface of therespective element. The first value, for example, 15%, 20%, 25% and/orthe like may be set to ensure that the selected paint material(s) is notsubstantially visible in the visible light spectrum when painted on theselected element(s).

Second, each of the selected paint materials may reflect light in theinfrared spectral range which is substantially different from theinfrared spectral range of the surface(s) of the selected object(s) onwhich the driving assistance markings are to be applied. Specifically,each paint material selected for painting the driving assistancemarkings should deviate by more than a second value from the infraredspectral range reflected by the respective surface of the respectiveelement. The second value, for example, 25%, 30%, 35% and/or the likemay be set to ensure that the selected paint material(s) issubstantially visible in the infrared light spectrum when painted on theselected element(s).

For brevity the paint material(s) selected for painting the drivingassistance markings are designated infrared reflective paint materials.However, the deviation in the reflectance of infrared light may be toboth directions, meaning that the paint material(s) selected forpainting the driving assistance markings may be more infrared reflectiveor more absorptive compared to the surrounding background of themarkings, i.e., the surface of the selected element(s) on which themarkings are painted. As such, when the selected infrared reflectivepaint material(s) is more infrared reflective, the driving assistancemarkings will reflect more infrared light compared to their surroundingbackground and will be thus visible in the infrared spectrum range.Never the less, when the selected infrared reflective paint material(s)is more infrared absorptive (less infrared reflective), the drivingassistance markings will reflect less infrared light compared to theirsurrounding background and will be also visible in the infrared spectrumrange.

For example, assuming the road markings engine 220 selects a certainblack asphalt road surface section of the road segment for applying thedriving assistance markings. Further assuming that while the blackasphalt road surface does not significantly reflect light in the visiblelight spectral range, the black asphalt road surface reflects infraredlight in a spectral range of, for example, less than 800 nm. In suchcase the road markings engine 220 may select a paint material which doesnot deviate from the black asphalt color by more than, for example, 20%meaning that it does not reflect more than 20% of the visible lightwhile significantly deviating, for example, by 25% from black asphaltcolor in the infrared spectral range, meaning that it reflects infraredlight in a range of more than 1000 nm for example.

In another example, assuming the road markings engine 220 selects acertain white road marking of the road segment for applying the drivingassistance markings. Further assuming that while the white road markingreflects most and possible all light in the visible light spectralrange, the white road marking reflects infrared light in a spectralrange of, for example, less than 950 nm. In such case the road markingsengine 220 may select a paint material which does not deviate from thewhite road marking by more than, for example, 20% meaning that itreflects more that 80% of the visible light while significantlydeviating, for example, by 25% from white road marking in the infraredspectral range, meaning that it reflects infrared light in a range ofmore than 1200 nm for example.

Reference is now made to FIG. 4, presents color blends (mixtures) of anexemplary infrared reflective paint material(s) visible in the infraredspectrum while imperceptible in the visible light spectrum used forpainting driving assistance markings, according to some embodiments ofthe present invention.

Assuming a road markings engine such as the road markings engine 220selects a certain infrared reflective paint material seen in 402 whichis characterized by a significantly dark color for painting drivingassistance markings generated for a certain road segment. Furtherassuming the road markings engine 220 selects to paint the drivingassistance markings on a certain element of the certain road segmentwhich is characterized by a white color as seen in 408. In such case,the road markings engine 220 may determine that the certain infraredreflective paint material should be mixed with one or more other paintmaterials, for example, a white paint material to ensure that thecertain infrared reflective paint material does not deviate from thecolor of the certain element painted white by more than the first value(e.g., 20%). The road markings engine 220 may compute one or moremixture ratios for mixing the certain infrared reflective paint materialsuch that the color of the mixed infrared reflective paint material doesnot deviate by more than the first value form the white color of thesurface of the certain element. A mixture at a ratio of 1:4 between thecertain infrared reflective paint material and the white paint materialis seen in 404 and a mixture at a ratio of 1:9 between the certaininfrared reflective paint material and the white paint material is seenin 406.

As shown at 112, the road markings engine 220 may compute instructionsfor painting the driving assistance markings generated for the roadsegment on the selected element(s) using the selected paint material(s).

For example, the painting instructions may indicate a location, aposition, an orientation, an elevation and/or the like for painting thedriving assistance markings on the selected element(s). In anotherexample, the painting instructions may indicate a size, a spacing and/orthe like of the painted driving assistance markings.

Moreover, the painting instructions may define mixing one or more of theselected inferred reflective paint materials with one or more otherpaint materials and/or dilution substances to achieve and comply withthe two characteristics of the paint material used to paint the drivingassistance markings. Namely, these two characteristics, as describedherein before, are deviation of less than the first value (e.g., 20%)from the visible light spectral range reflected by the surface of therespective element and deviation of more than the second value (e.g.,25%) from the infrared spectral range reflected by the surface of therespective element. The painting instructions may therefore define aconcentration of each of the paint materials in the mixture, a volume ofeach paint materials in the mixture, one or more dilution materialsand/or the like.

Optionally, the road markings engine 220 computes instructions forpainting one or more of the driving assistance markings on the selectedelement(s) in close proximity, specifically closely around one or morevisible road markings, for example, lane separator markings, road sideborder line markings, pedestrian crossings, painted direction symbols(e.g., arrows, stop lines, etc.), painted text (e.g. stop, slow, etc.)and/or the like. For example, the road markings engine 220 may computeinstructions for painting one or more of the driving assistance markingsnext to lane separator lines markings. In another example, the roadmarkings engine 220 may compute instructions for painting one or more ofthe driving assistance markings around one or more direction arrowmarkings. Painting the infrared visible driving assistance markings inproximity to the visible road markings may enable the automatedvehicular systems to more easily detect, identify and/or recognize theinfrared visible driving assistance markings. In particular, since theinfrared visible driving assistance markings are located in proximity tothe visible road markings, the automated vehicular systems may noterroneously interpret arbitrary infrared reflective materials and/orsections of the road segment as the infrared visible driving assistancemarkings.

The road markings engine 220 may compute the instructions for paintingthe driving assistance markings using the infrared reflective paintmaterial(s) on existing painted surfaces of the selected element(s) ofthe road segment. For example, assuming there are lane separator linemarkings painted in at least part of the road segment, the road markingsengine 220 may compute the instructions for painting the drivingassistance markings using the infrared reflective paint material(s) onthe existing lane separator line markings and/or part thereof. Inanother example, assuming there are one or more painted traffic polesand/or traffic light poles in the road segment, the road markings engine220 may compute the instructions for painting the driving assistancemarkings using the infrared reflective paint material(s) on one or moreof the painted poles.

However, the road markings engine 220 may compute the instructions forpainting the driving assistance markings using the infrared reflectivepaint material(s) in conjunction with one or more other paint materialsused to paint the surface(s) of the selected element(s). For example,the road markings engine 220 may compute instructions for painting oneor more visible road markings, for example, lane separator lines,pedestrian crossing, direction symbols and/or the like using one or morevisible light paint materials, for example, white paint. The roadmarkings engine 220 may further compute instructions for using theinfrared reflective paint material(s) to paint the driving assistancemarkings over one or more of the newly painted white road markings. Inanother example, the road markings engine 220 may compute instructionsfor painting one or more traffic poles located in the road segment usingone or more visible light paint materials, for example, gray paint. Theroad markings engine 220 may further compute instructions for using theinfrared reflective paint material(s) to paint the driving assistancemarkings over the one or more of the newly painted poles.

As shown at 114, the road markings engine 220 may output the paintinginstructions computed for painting the driving assistance markings onone or more of the elements of the road segment using one or more of theinfrared visible paint materials

The road markings engine 220 may output the painting instructions in oneor more formats. For example, the painting instructions may be generatedand configured accordingly to instruct one or more workers to manuallyapply the infrared visible paint(s). In another example, the paintinginstructions may be directed and configured accordingly for one or moreautomated painting systems, apparatuses and/or devices configured toapply automatically the infrared visible paint(s) to paint.

Reference is now made to FIG. 5, which presents images of a road sectionpainted with an exemplary paint material(s) visible in the infraredspectrum while imperceptible in the visible light spectrum used forpainting driving assistance markings, according to some embodiments ofthe present invention.

As seen in 502 which is an image of an exemplary certain road sectioncaptured in visible light spectral range, a certain mark 510 is almostimperceptible since it is painted using an exemplary infrared reflectivepaint material which does not significantly deviate from the color(visible light spectral range) of the certain road section.

As seen in 504, which is an image of the certain road section capturedin NIR infrared spectral range, specifically at 850 nm, the certain mark510 is slightly more visible since the exemplary infrared reflectivepaint material deviates to some extent from the infrared spectral rangeof the certain road section. However, the deviation may be insufficient,i.e., less than the second value (e.g. 25%) such that it may besignificantly difficult to distinguish the certain mark 510 from itssurrounding road section even in the 850 nm spectral range.

As seen in 506, which is an image of the certain road section capturedin higher NIR infrared spectral range, specifically at 850-1050 nm, thecertain mark 510 is highly visible since the exemplary infraredreflective paint material significantly deviates from the infraredspectral range of the certain road section, specifically by more thanthe second value (e.g. 25%).

According to some embodiments of the present invention the road markingsgeneration system 200, specifically the road markings engine 220 may beintegrated and/or executed by one or more painting systems, apparatusesand/or devices configured to apply automatically one or more of theinfrared reflective paint materials for painting the infrared visibledriving assistance markings on one or more elements in one or more roadsegments.

Such painting systems, apparatuses and/or devices, collectivelydesignated automated painting systems herein after, may be equipped withone or more paint applying elements as known in the art, for example, asprayer, a brush, a dispenser and/or the like which are controllable byone or more controllers and/or processors of the automated paintingsystems.

The road markings engine 220 executed by one or more of the automatedpainting systems may therefore execute the process 100 to compute theinstructions for painting the driving assistance markings generated forone or more road segments on one or more elements of the respective roadsegments using one or more of the infrared reflective paint materials.

Specifically, one or more of the automated painting systems may beequipped with one or more imaging sensors, for example, a camera,infrared camera, a thermal camera and/or the like configured to captureone or more images of the road segment(s) in particular of one or moreof the elements of the road segment(s). The road markings engine 220 mayanalyze the images, specifically the elements' surface(s) to identifytheir color and select the infrared reflective paint material(s)accordingly as described in the process 100.

After computing the painting instructions, the road markings engine 220may operate one or more of the paint applying elements of the respectiveautomated paining system to automatically apply the infrared reflectivepaint materials in order to paint the infrared visible drivingassistance markings. In other embodiments, the road markings engine 220may provide the painting instructions to one or more other functionalmodules (e.g. software module, hardware element and/or a combinationthereof) executed by the automated painting system.

Optionally, one or more of the automated paining systems may be furtherconfigured to apply visible paint to paint road markings using one ormore visible paint materials which are visible in the visible lightspectrum. Such automated paining systems may optionally paint theinfrared visible driving assistance markings using the selected infraredreflective paint material(s) while painting the visible road markingsusing the visible paint material(s).

According to some embodiments of the present invention, the roadmarkings generation system 200, specifically the road markings engine220 may be configured to compute instructions for painting roadmarkings, specifically background patterns on one or more surfaces ofone or more road segments which are highly visible in one or moreinfrared light spectral ranges while highly imperceptible in the visiblelight spectrum.

The background patterns are painted to support object detection,specifically, detection of dynamic objects, for example, vehicles,pedestrians and/or the like which may move in the road segments and thuscross surfaces of the road segments on which the background patters maybe painted, for example, a road surface, a sidewalk surface and/or oneor more surfaces of practically any other transportation infrastructureobject such as, for example, traffic signs, road signs, poles, barrierrails, bridges and/or the like.

The background patterns may be painted such that, in the visible lightspectral range, the background patterns may significantly blend withtheir background, i.e. the surfaces on which they are painted thusmaking them significantly imperceptible by the human eye and thusinvisible to human drivers and/or visible light based automated systems.However, in one or more of the infrared light spectral ranges, forexample, NIR, SWIR and/or the like, the background patterns may behighly visible over the painted surfaces as they may reflect infraredlight very differently from the infrared reflection characteristics ofthe surfaces.

Moreover, the infrared light reflected by the background patterns may bealso very different from the infrared light reflected by the dynamicobjects. Therefore, when crossing the background patterns and located infront of them, the dynamic objects may be highly detectable in theinfrared spectral range(s) as the infrared light they reflect may beeasily distinguish them from the background patterns.

The road markings engine 220 may execute a process similar to theprocess 100 to paint the background patterns on one or more surfaces ofone or more road segments. However, the road markings engine 220 mayexecute the process 100 with some adjustments. First, in step 104, theroad markings engine 220 may compute background patterns estimated tobest support efficient detection of dynamic objects moving in the roadsegment. Moreover, in step 106, the road markings engine 220 maytypically select surfaces which are estimated to be crossed by one ormore of the dynamic objects such that the dynamic objects may bedetected when located in front of one or more of the backgroundpatterns.

Furthermore, in step 110, the road markings engine 220 may optionallyselect multiple paint materials which reflect significantly differentlight levels in one or more of the infrared spectral ranges, forexample, NIR, SWIR and/or the like while in the visible light spectralrange they may reflect light which deviates by less than a certain valuefrom the light reflected by the selected surface. This may serve topaint background patterns which may alternate in the infrared lightreflection such that even if one or more of the dynamic objects reflectinfrared light which does not significantly deviate from the infraredlight reflected by background pattern(s) painted with one of the paintmaterials this dynamic object(s) may be highly detectable when located(crossing) in front of background pattern(s) painted with one or moreother paint materials having different infrared reflectioncharacteristics.

Optionally, the road markings engine 220 may select one or more paintmaterial which are at least partially and typically highly transparentin one or more of the infrared spectral ranges, for example, NIR, SWIRand/or the like while reflecting light in the visible light range whichdoes not significantly deviates from the light reflected by thesurfaces(s) selected for painting the background pattern(s). This meansthat in the visible light range, the selected paint material(s) mayreflect light which deviates by less than the first value from thevisible light reflected by the surface(s). However, in the infraredspectral range(s) (e.g. NIR, SWIR), the selected paint material(s) maytransfer more than a fourth value of light, for example, 80%, 85, %,90%, 95% and/or the like.

One or more of the background patterns may be painted on the selectedsurface(s) which may be further painted using the at least partiallyinfrared transparent paint material(s) such that background pattern(s)are painted beneath the at least partially infrared transparent paintmaterial(s). The background pattern(s) may be painted using one or morepaint materials visible in one or more spectral ranges, for example, thevisible light spectrum, the NIR spectral range, the SWIR spectral rangeand/or the like. As such, in the infrared spectral range(s) theoverlaying at least partially infrared transparent paint material may betransparent thus exposing the background pattern(s) painted on theselected surface(s) beneath the at least partially infrared transparentpaint material.

As describe in the process 100, in step 102, the road markings engine220 may receive one or more images of the road segment.

In step 104, the road markings engine 220 may generate one or morebackground patterns for the road segment. In particular, the roadmarkings engine 220 may create, based on analysis of the image(s), oneor more background patterns estimated to best support detection of oneor more dynamic objects, for example, a vehicle, a pedestrian and/or thelike while crossing he backgrounds patterns.

The background patterns generated by the road markings engine 220 mayinclude, one or more patterns, symbols and/or the like which may haveone or more shapes, dimensions (e.g. length, width, etc.) which areestimated to best support detection of one or more dynamic objects, forexample, a vehicle, a pedestrian and/or the like while crossing hebackgrounds patterns.

In step 106, the road markings engine 220 may analyze the image(s) ofthe road segment to identify and select one or more surfaces, forexample, a road surface, a sidewalk surface and/or a surface of one ormore other transportation infrastructure objects, for example, a trafficsign, a road sign, a pole, a barrier rail, a bridges and/or the like onwhich the background pattern(s) are to be applied (painted).

In step 108, the road markings engine 220 may analyze the selectedsurface(s) on which the background pattern(s) generated for the roadsegment are to be painted. In particular, the road markings engine 220may analyze the image(s) of the road segment to identify a color of theselected surface(s) and more specifically to identify the spectral rangeof visible light reflected by the selected surface(s), for example,visible light corresponding to black color, gray color, white color,blue color, red color and/or the like.

In step 110, the road markings engine 220 may select one or more paintmaterials for painting the background pattern(s) generated for the roadsegment on the selected surface(s) of the road segment.

The background pattern(s) are directed to support one or more objectdetection systems configured to monitor traffic, vehicles, pedestriansand/or the like, for example, a speed control system, a traffic offensesdetection systems, a pedestrian safety system and/or the like which arecapable of operating in the infrared spectrum. These object detectionsystem(s), which are typically automated systems, may integrate, employ,connect and/or communicate with one or more imaging sensors, forexample, a camera, an infrared camera, a thermal mapping camera, a LiDARsensor and/or the like configured to capture images of the road segmentin one or more of the infrared spectral ranges, for example, NIR, SWIRand/or the like.

Therefore, for painting the background pattern(s) the road markingsengine 220 may select paint one or more paint materials which reflect(or absorb) infrared light in one or more of the infrared spectralranges. However, while the selected paint material(s) are characterizedby reflecting and/or absorbing significant light in the infrared lightspectral range(s), these paint materials are also characterized byreflecting light, in visible light spectral range, which issubstantially similar to the light reflected by the selected surface onwhich the background pattern(s) are to be painted.

In the visible light range, the selected paint material(s) may thereforereflect light deviating by less than a first value from the lightreflected by the selected surface(s). The first value, for example, 15%,20%, 25% and/or the like may be set to ensure that the backgroundpattern(s) painted using the selected paint material(s) blends with thesurface and is thus substantially imperceptible (invisible) in thevisible light spectrum.

Complementary, the selected paint material(s) may reflect infraredlight, in one or more of the infrared spectral ranges, which issubstantially different from the infrared light reflected by theselected surface(s). Specifically, each selected paint material maydeviate by more than a second value from the infrared spectral rangereflected by the selected surface(s). The second value, for example,20%, 25%, 30% and/or the like may be set to ensure that the backgroundpattern(s) painted using the selected paint material(s) is substantiallydistinguishable from the selected surface(s) and is thus perceptible(visible) in the infrared light spectral range(s).

Optionally, a plurality of paint materials may be selected to paint aplurality of alternating background patterns, for example, two, threeand/or the like such that different background patterns, typicallyadjacent background patterns are painted using different paint materialshaving very different infrared reflection characteristics. The lightreflected by each selected paint material in one or more of the infraredspectral ranges may therefore deviate by more than a third value fromthe infrared light reflected by any of the other selected paintmaterials, for example, 20%, 25%, 30% and/or the like.

Painting the alternating background patterns may increase detectionperformance, for example, accuracy, reliability, robustness and/or thelike of one or more of the object detection systems since even if one ormore of the dynamic objects reflect infrared light which does notsignificantly deviate from the infrared light reflected by thebackground pattern(s) painted using a selected first paint material, theinfrared light reflected by the dynamic object(s) may significantlydeviate from the infrared light reflected by the background pattern(s)painted using a selected second paint material which is different in itsinfrared reflection characteristics from the first paint material,specifically by the third value.

Reference is now made to FIG. 6A and FIG. 6B, which illustrate exemplaryroad markings painted using paint material(s) visible in the infraredspectrum while imperceptible in the visible light spectrum used forpainting additional road markings, according to some embodiments of thepresent invention.

As seen in FIG. 6A, an image 602A presents a certain pattern 610 paintedon a road surface as captured in the visible light spectral range whilean image 602B presents the same pattern 610 captured in an infraredspectral range, for example, NIR. As evident in the image 602A, thepattern 610 substantially blends with the background road surface as itmay reflect visible light deviating by less than the first value fromthe visible light reflected by the road surface. However, as seen in theimage 602B, the infrared light reflected by the pattern 610 in theinfrared spectral range significantly deviates from the infrared lightreflected by the road surface, specifically by the second value and istherefore highly distinguishable from the road surface.

Moreover, as seen in image 602B, the pattern 610 is painted using twoinfrared reflective paint materials which significantly deviate in theirinfrared reflection characteristics, specifically by the third value andare therefore highly distinguishable from each other forming analternating background pattern comprising infrared light high reflectionsections (brighter) and infrared light low reflection sections (darker).

As seen in FIG. 6B, an image 604A presents a certain pattern 612 paintedon a road surface as captured in the visible light spectral range whilean image 604B presents the same pattern 612 captured in an infraredspectral range, for example, NIR.

As seen in the image 604A, in the visible light spectrum tow outer linesof the pattern 612 seem the same as they are painted using paintmaterials which in the visible light may reflect substantially the samelight range (color). However, as seen in the image 604B, in the infraredspectral range, the further section of the outer lines of the pattern612 seem significantly brighter compared to the closer section of theouter lines of the pattern 612 which seem much darker. This is becausethe further and closer sections of the outer line o of the pattern 612are painted using two different infrared reflective paint materialswhich significantly deviate in their infrared reflectioncharacteristics, specifically by the third value and are thereforehighly distinguishable from each other.

In step 112, the road markings engine 220 may compute instructions forpainting the background pattern(s) generated for the road segment on theselected surfaces of the road segment.

For example, the painting instructions may indicate a location, aposition, an orientation, an elevation and/or the like for painting thebackground pattern(s) on the selected surface(s). In another example,the painting instructions may indicate a size, a spacing and/or the likeof the painted background pattern(s).

Moreover, the painting instructions may define mixing one or more of theselected inferred reflective paint materials with one or more otherpaint materials and/or dilution substances to achieve and comply withthe two characteristics of the paint material used to paint the drivingassistance markings. Namely, deviation of less than the first value(e.g., 20%) from the visible light spectral range reflected by theselected surface(s) and deviation of more than the second value (e.g.,25%) from the infrared spectral range reflected by the selectedsurface(s) of the respective element. The painting instructions maytherefore define a concentration of each of the paint materials in themixture, a volume of each paint materials in the mixture, one or moredilution materials and/or the like.

The road markings engine 220 may optionally compute instructions forpainting the driving assistance markings using the infrared reflectivepaint material(s) on one or more already painted selected surfaces ofthe road segment. For example, assuming there are lane separator linemarkings painted on a road surface in at least part of the road segment,the road markings engine 220 may compute instructions for painting thebackground pattern(s) using the infrared reflective paint material(s) onthe existing lane separator line markings and/or part thereof.

Moreover, the road markings engine 220 may compute the instructions forpainting the background pattern(s) using the infrared reflective paintmaterial(s) in conjunction with one or more other paint materials usedto paint the selected surface(s). For example, the road markings engine220 may compute instructions for painting one or more visible roadmarkings, for example, lane shoulder lines, pedestrian crossing,direction symbols and/or the like using one or more visible light paintmaterials, for example, white paint. The road markings engine 220 mayfurther compute instructions for using the infrared reflective paintmaterial(s) to paint the background pattern(s) over one or more of thenewly painted white road markings.

In step 114, the road markings engine 220 may output the paintinginstructions computed for painting the background pattern(s) on one ormore of the selected surfaces of the road segment using one or more ofthe selected infrared reflective paint materials.

Reference is now made to FIG. 7A and FIG. 7B, which present exemplarybackground patterns painted in an exemplary road segment using paintmaterial(s) visible in the infrared spectrum while imperceptible in thevisible light spectrum, according to some embodiments of the presentinvention;

FIG. 7A is an image of a certain road segment 702 captured in thevisible light spectral range while FIG. 7B is an image of the 602Bpresents the same road segment 702 captured in an infrared spectralrange, for example, NIR.

As seen in the image in FIG. 7B, a plurality of background patterns 710,for example, background patterns 710A, 710B, 710C, 710D, 710E and 710Fwhich are painted on the road surface of the road segment 702 usinginfrared reflective paint materials are highly visible in the infraredspectral range. However, as seen in the image in FIG. 7A, the backgroundpatterns 710A, 710B, 710C, 710D, 710E and 710F blend with the backgroundroad surface 702 and are thus highly imperceptible (and practicallyinvisible) in the visible light spectral range.

Moreover, the background patterns 710 are painted using two distinctinfrared reflective paint materials which reflect infrared lightdeviating by more than the third value compared to each other suchalternating background patterns 710 are significantly distinguishablefrom each other. For example, the background patterns 710A, 710C and710E painted using a first high infrared light reflection paint materialseem much brighter compared to the background patterns 710B, 710D and710F painted using a second low infrared light reflection paint material(infrared absorptive material) which appears much darker.

According to some embodiments of the present invention, one or more ofthe object detection systems may be configured to detect traffic of oneor more of the dynamic objects, for example, a vehicle, a pedestrianand/or the like crossing and thus located in front of backgroundpatterns painted on one or more surfaces of one or more road segments.

Reference is now made to FIG. 8, which is a flowchart of an exemplaryprocess of detecting dynamic objects crossing background patternspainted using infrared reflective paint material(s), according to someembodiments of the present invention. Reference is also made to FIG. 9,which is a schematic illustration of an exemplary system for detectingdynamic objects crossing background patterns painted using infraredreflective paint material(s), according to some embodiments of thepresent invention.

An object detection system, device, apparatus and/or the likecollectively designated object detection system 900 may be configured toexecute an exemplary process 800 to detect one or more dynamic objectsin one or more road segments, specifically road segments painted withone or more background patterns which are highly visible in the infraredspectral range(s) while highly imperceptible in the visible lightspectral range.

The object detection system 900 may include an I/O interface 910 such asthe I/O interface 210, a processor(s) 912 such as the processor(s) 212for executing the process 800 and a storage 914 such as the storage 214for storing data and/or code (program store).

Via the I/O interface 910, interface comprising one or more networkinterfaces and/or interconnection interfaces, the object detectionsystem 900 may connect and/or communicate with one or more othersystems, devices and/or services which may be local and/or remote, forexample, a remote server, a cloud service, a cloud platform and/or thelike.

Specifically, via the I/O interface 910, the object detection system 900may communicate with one or more imagining sensors 902 deployed andconfigured to monitor and capture images of the road segment. Theimaging sensors 902 may include, for example, the camera, the infraredcamera, the thermal mapping camera and/or the like configured to captureimages of the vehicle's surroundings in one or more of the infraredspectral ranges, for example, NIR, SWIR and/or the like.

The processor(s) 912 may execute one or more software modules such as,for example, a process, a script, an application, an agent, a utility, atool, an OS and/or the like each comprising a plurality of programinstructions stored in a non-transitory medium (program store) such asthe storage 914 and executed by one or more processors such as theprocessor(s) 912. The processor(s) 912 may optionally, integrate,utilize and/or facilitate one or more hardware elements (modules)integrated and/or utilized in the road markings generation system 200,for example, a circuit, a component, an IC, an ASIC, an FPGA, a DSP, aGPU and/or the like.

The processor(s) 912 may therefore execute one or more functionalmodules implemented using one or more software modules, one or more ofthe hardware modules and/or combination thereof. For example, theprocessor(s) 912 may execute a detection engine 920 functional moduleconfigured to execute the process 800 for detecting dynamic objects inthe road segment painted with one or more background patterns highlyvisible in the infrared spectral range(s) while highly imperceptible inthe visible light spectral range.

Optionally, the object detection system 900, specifically the detectionengine 920 are provided and/or utilized by one or more cloud computingservices, for example, IaaS, PaaS, SaaS and/or the like provided by oneor more cloud infrastructures, platforms and/or services such as, forexample, Amazon AWS, Google Cloud, Microsoft Azure and/or the like. Insuch deployments, the detection engine 920 may communicate with theimaging sensor 902 via one or more networks to receive images of theroad segment captured by the imaging sensors 902.

As shown at 802, the object detection system 900, specifically thedetection engine 920 may receive one or more images of the road segmentcaptured by the imaging sensor(s) 902.

Since the imaging sensor(s) 902 are configured to operate in theinfrared spectral range(s) (e.g. NIR, SWIR, etc.), the received imagesmay depict the road segment and hence the background pattern(s) paintedon one or more surfaces of the road segment in one or more of theinfrared spectral ranges.

Each of the imaging sensor(s) 902 may be typically deployed elevatedabove ground level such that its Field of View (FOV) may include asignificant portion of the road segment stretching away from a locationof the respective imaging sensor 902. The images captured by the imagingsensor(s) 902 may therefore capture a significant portion of roadsegment potentially to far distance from the imaging sensor(s) 902.

As shown at 804, the detection engine 920 may analyze the image(s)depicting at least part of the road segment painted with one or morebackground patterns to identify one or more dynamic objects, forexample, a vehicle, a pedestrian and/or the like moving in the roadsegment.

In particular, the detection engine 920 may analyze the image(s) toidentify one or more dynamic objects which cross one or more of thebackground pattern(s) painted in the road segment such that the crossingdynamic object(s) and/or part thereof is located in front of one or moreof the background pattern(s) painted on one or more surfaces of the roadsegment.

The detection engine 920 may analyze the image(s) using one or moremethods, techniques and/or algorithms as known in the art, for example,computer vision, image processing, classification functions(classifiers), machine learning models and/or the like.

As described herein before, the background patterns may be painted usinga plurality of paint materials reflecting infrared light whichsignificantly deviates from one paint material to another. The detectionengine 920 may therefore detect one or more dynamic objects reflectinginfrared light which is substantially similar to the infrared lightreflected by one of the paint materials used to one or more of thebackground patterns. In particular, the detection engine 920 may detectsuch dynamic object(s) while located in front of other backgroundpattern(s) painted using another paint material reflecting infraredlight significantly deviating from the infrared light reflected by thedynamic object(s).

For example, assuming detection engine 920 analyzes image(s) depictingthe road surface 702 painted with the background patterns 701A, 701B,710C, 710D, 710E and 710F. Further assuming that a certain dynamicobject, for example, a car moving on the road surface 702 towards theimaging sensor 902 which captured the image 7B reflects infrared lightwhich is very similar to the infrared light reflected by some of thebackground patterns, for example, the bright background patterns 710A,710C and 710E. In such case, the detection engine 920 may fail to detectthe car while crossing the bright background patterns 710A, 710C and710E. However, the detection engine 920 may detect the car whilecrossing the dark background patterns 710B, 710D and/or 710F since thelight reflected by the dark background patterns 710B, 710D and/or 710Fin the infrared spectral range(s) deviates by more than the third valuefrom the inferred light reflected by the bright background patterns710A, 710C and 710E and hence also from the inferred light reflected bythe crossing car. The detection engine 920 may therefore easily detectthe car while highly visible in the inferred spectral range(s) comparedto its background dark background patterns 710B, 710D and/or 710F.

As shown at 806, the detection engine 920 may compute a location of eachidentified dynamic object.

The physical position of the imaging sensor(s) 902, for example,location, elevation and/or the like may be known. One or more imagecapturing parameters of the imaging sensor(s) 902 may be also known, forexample, resolution, pixel size and/or the like. The detection engine920 may therefore derive real world dimensions, location and/or positionbased on pixel conversion of the captured images as known in the art.

Therefore, based on the analysis of the image(s) depicting one or moredynamic images located in front of one or more of the backgroundpattern(s) painted on one or more surfaces of the road segment andfurther based on the conversion ratio, the detection engine 920 maycompute the real-world location of each detected dynamic object.

Optionally, the detection engine 920 may further compute one or moreattributes of one or more of the detected dynamic objects, for example,one or more dimensions such as, for example, size, length, width, heightand/or the like, speed, acceleration direction of movement (movementvector) and/or the like. To this end, the detection engine 920 may applyimage analysis, computation and conversion of pixel size to real-worlddimensions based on the known location, position, orientation and/or ofthe imaging sensor(s) coupled with their image capturing parameters asknown in the art.

According to some embodiments of the present invention, there areprovided methods, systems and computer program products for computinginstructions for painting, in one or more road segments, referencemarkings which are highly perceptible (visible) in one or more of theinfrared spectral ranges, for example, NIR, SWIR and/or the like whilehighly imperceptible (invisible) in the visible light spectral range.

The reference markings which may be painted on one or more surfaces ofthe road segment(s) are directed to support calibration of one or moreimaging sensors such as the imaging sensor 902 deployed to captureimagery data of the road segments that are later used by the objectdetection system(s) 900. The reference markings which may be alsopainted with respect to one or more elements of the road segment, forexample, intersection entry/exit points, lane separators, stop lines,pedestrian crossings and/or the like. The reference markings may furtherinclude and/or encode an identifier of the road segment which mayinclude, for example, identification data of the road segment, a type ofthe road segment, a location of the road segment, (e.g. longitude,latitude, altitude, etc.) and/or the like.

These reference markings may be used by one or more object detectionsystems such as the object detection system 900, for example, a trafficmonitoring systems such as, for example, a traffic control system, avehicle speeding detection system, a red-light crossing detection systemand/or the like to improve their detection of the elements marked by thereference markings.

The road markings engine 220 may execute a process similar to theprocess 100 to paint the reference markings on one or more surfaces ofone or more road segments with some adjustments. First, the step 102 isoptional. While the road markings engine 220 may receive images andanalyze them to automatically identify where to place the referencemarkings in the road segment, the markings engine 220 receiveinstructions, for example, from an expert user for the locations atwhich the reference markings are to be painted. In step 104, the roadmarkings engine 220 may compute reference markings estimated to bestsupport efficient calibration of the imaging sensor(s) 902 deployed tomonitor the road segment and/or of elements of value to the trafficmonitoring system(s) deployed to monitor the road segment.

As describe in the process 100, in step 102, the road markings engine220 may receive one or more images of the road segment.

In step 104, the road markings engine 220 may generate one or morereference markings for the road segment which may follow one or morepatterns, symbols and/or the like having one or more shapes, dimensions(e.g. length, width, etc.) estimated by the road markings engine 220based on analysis of the image(s) to best support calibration of theimaging sensor(s) 902 and/or the traffic monitoring system(s) deployedto monitor the road segment.

In step 106, the road markings engine 220 may analyze the image(s) ofthe road segment to identify and select one or more surfaces, forexample, a road surface, a sidewalk surface and/or a surface of one ormore other transportation infrastructure objects, for example, a trafficsign, a road sign, a pole, a barrier rail, a bridges and/or the like onwhich the reference markings are to be applied (painted).

In step 108, the road markings engine 220 may analyze the selectedsurface(s) on which the reference markings generated for the roadsegment are to be painted. In particular, the road markings engine 220may analyze the image(s) of the road segment to identify a color of theselected surface(s) and more specifically to identify the spectral rangeof visible light reflected by the selected surface(s), for example,visible light corresponding to black color, gray color, white color,blue color, red color and/or the like.

In step 110, the road markings engine 220 may select one or more paintmaterials for painting the reference markings generated for the roadsegment on the selected surface(s) of the road segment.

The reference markings are directed to support calibration of imagingsensor(s) 902 and/or detection capabilities of one or one or more objectdetection systems such as the object detection system 900 configured tomonitor traffic, vehicles, pedestrians and/or the like, for example, aspeed control system, a traffic offenses detection systems, a pedestriansafety system and/or the like. Specifically, the reference markings aredirected to support imaging sensor(s) 902 and traffic control system(s)900 which are capable of operating in one or more of the infraredspectral ranges, for example, NIR, SWIR and/or the like.

Therefore, for painting the reference markings the road markings engine220 may select paint one or more paint materials which reflect (orabsorb) infrared light in one or more of the infrared spectral ranges.However, while the selected paint material(s) are characterized byreflecting and/or absorbing significant light in the infrared lightspectral range(s), these paint materials are also characterized byreflecting light, in visible light spectral range, which issubstantially similar to the light reflected by the selected surface onwhich the reference markings are to be painted.

In the visible light range, the selected paint material(s) may thereforereflect light deviating by less than a first value from the visiblelight spectral range reflected by the selected surface(s). The firstvalue, for example, 15%, 20%, 25% and/or the like may be set to ensurethat the reference markings painted using the selected paint material(s)blends with the surface and is thus substantially imperceptible(invisible) in the visible light spectrum.

Complementary, the selected paint material(s) may reflect light in oneor more of the infrared spectral ranges which is substantially differentfrom the infrared spectral range reflected by the selected surface(s).Specifically, each selected paint material may deviate by more than asecond value from the infrared spectral range reflected by the selectedsurface(s). The second value, for example, 20%, 25%, 30% and/or the likemay be set to ensure that the reference markings painted using theselected paint material(s) is substantially distinguishable from theselected surface(s) and is thus perceptible (visible) in the infraredlight spectral range(s).

Optionally, a plurality of paint materials may be selected to paint thereference markings, for example, two, three and/or the like each havingdifferent infrared reflection characteristics.

Optionally, the road markings engine 220 may select one or more of theat least partially infrared transparent paint materials which are atleast partially and typically highly transparent in the infraredspectral range(s) (e.g. NIR, SWIR, etc.) while reflecting light in thevisible light range which does not significantly deviates from the lightreflected by the surfaces(s) selected for painting the referencemarkings. As such, in the visible light range, the selected paintmaterial(s) may reflect light which deviates by less than the firstvalue from the visible light reflected by the selected surface(s) whilein the infrared spectral range(s), the selected paint material(s) maytransfer more than the fourth value of (infrared) light.

One or more of the reference markings may be therefore painted on theselected surface(s) which may be further painted using the at leastpartially infrared transparent paint material(s) such that referencemarkings are painted beneath the at least partially infrared transparentpaint material(s). The reference markings may be painted using one ormore paint materials visible in one or more spectral ranges, forexample, the visible light spectrum, the NIR spectral range, the SWIRspectral range and/or the like. In the infrared spectral range(s) theoverlaying at least partially infrared transparent paint material maybecome transparent thus exposing the reference markings painted on theselected surface(s) beneath the at least partially infrared transparentpaint material.

In step 112, the road markings engine 220 may compute instructions forpainting the reference markings generated for the road segment on theselected surfaces of the road segment.

For example, the painting instructions may indicate a location, aposition, an orientation and/or the like for painting the referencemarkings on the selected surface(s). In another example, the paintinginstructions may indicate a size, a spacing and/or the like of thepainted reference markings.

Moreover, the painting instructions may define mixing one or more of theselected inferred reflective paint materials with one or more otherpaint materials and/or dilution substances to achieve and comply withthe two characteristics of the paint material used to paint the drivingassistance markings. The road markings engine 220 may optionally computeinstructions for painting the driving assistance markings using theinfrared reflective paint material(s) on one or more already paintedselected surfaces of the road segment. Moreover, the road markingsengine 220 may compute the instructions for painting the backgroundpattern(s) using the infrared reflective paint material(s) inconjunction with one or more other paint materials used to paint theselected surface(s).

In step 114, the road markings engine 220 may output the paintinginstructions computed for painting the reference markings on one or moreof the selected surfaces of the road segment using one or more of theselected infrared reflective paint materials.

One or more traffic monitoring systems which may use and objectdetection system such as the object detection system 900 may use thereference markings painted in one or more road segments. For example,one or more imaging sensor 902 used by the object detection system 900may be calibrated according to one or more of the reference markings. Inanother example, the traffic monitoring system(s) may use referencemarkings indicative of the road segment elements (e.g. stop lines, laneseparators, etc.) to accurately identify them in particular with respectto dynamic objects detected in the road segment.

Reference is now made to FIG. 10, which is an exemplary process ofcalibration based on road reference markings painted using paintmaterial(s) visible in the infrared spectrum while imperceptible in thevisible light spectrum, according to some embodiments of the presentinvention.

An object detection system such as the object detection system 900,specifically an object detection system 900 used by one or more trafficmonitoring systems deployed to monitor a road segment may be configuredto execute a detection engine such as the detection engine 920 forexecuting an exemplary process 1000. The detection engine 920 mayexecute the process 1000 to calibrate the object detection system 900,the detection engine 920 and/or one or more imaging sensors such as theimaging sensor 902 deployed to monitor the road segment according toroad reference markings painted in the road segment which are highlyvisible in the infrared spectral range(s) while highly imperceptible inthe visible light spectral range.

As shown at 1002, the object detection system 900, specifically thedetection engine 920 may receive one or more images of the road segmentcaptured by the imaging sensor(s) 902.

As the imaging sensor(s) 902 may be configured to operate in one or moreof the infrared spectral ranges, for example, NIR, SWIR and/or the like,the images depicting the road segment may further depict one or morereference markings painted on one or more surfaces of the road segmentusing one or more pant materials which reflect visible light deviatingby less than the first (e.g. 15%, 20%, 25%, etc.) from the visible lightspectral range reflected by the respective surface while reflectinginfrared light deviating by more than the second value (e.g. 20%, 25%,30% etc.) from the infrared light reflected by the respective surface.

As shown at 1004, the detection engine 920 may analyze the image(s)depicting at least part of the road segment to identify one or morereference markings painted in the road segment. The detection engine 920may analyze the image(s) using one or more of the methods, techniquesand/or algorithms known in the art for image analysis and objectdetection, for example, computer vision, image processing, classifiers,machine learning models and/or the like.

As shown at 1006, the detection engine 920 may calibrate the objectdetection system 900, the detection engine 920 itself and/or one or moreof the imaging sensors 902 deployed to monitor the road segment.

For example, one or more of the imaging sensors 902 may be calibrated,for example, adjust their alignment, reference plane, orientation and/orthe like according to one or more attributes of one or more of thereference markings, for example, location, position, orientation,dimension(s) and/or the like. For example, a certain imaging senor 902may be calibrated according to its distance, position and/or orientationcompared to one or more reference markings detected in the images. Inanother example, the object detection system 900, the detection engine920 may be calibrated and/or adjusted to align according to one or moreelements (e.g. stop lines, lane separators, intersection entry/exitpoints, etc.) of the road segment which are indicated by one or more ofthe reference markings identified in the images of the road segment.

In another example, the detection engine 920 may extract the identifierof the road segment encoded in one or more of the reference markings.The detection engine 920 may further access one or more data records,for example, a file, a database, a cloud service and/or the likeassociating road segment with respective data, for example, dimensionsof the road segment, location of one or more of the road segmentelements and/or the like. The data record(s) may be stored locally (e.g.in the storage 914) and/or remotely in one or more networked resourcesaccessible via the I/O interface 910. The detection engine 920 maytherefore fetch the data associated with the road segment identified byits extracted identifier and may use the fetched data to calibrateitself, the object detection system 900, the traffic monitoringsystem(s) and/or one or more of the imaging sensor(s) 902.

Reference is now made to FIG. 11A and FIG. 11B, which present exemplaryreference markings painted in an exemplary intersection using paintmaterial(s) visible in the infrared spectrum while imperceptible in thevisible light spectrum, according to some embodiments of the presentinvention.

FIG. 11A and FIG. 11B present an exemplary road segment, specifically a4-way intersection 1100 controlled by traffic lights from all directionsin which a plurality of vehicles, for example, cars, truck, bicycles,buses and/or the like as well as pedestrians may travel and move around.

As seen in the image in FIG. 11A depicting the intersection 1100 invisible light range, a traffic monitoring system incorporating and/orutilizing an object detection system such as the object detection system900 deployed to monitor traffic in the intersection 1100 may receiveimages from one or more imaging sensors such as the imaging sensor 902deployed to monitor the intersection 1100.

For example, the traffic monitoring system utilizing the objectdetection system 900 may be configured detect, track, monitor andoptionally analyze and generate reports relating to vehicle traffic,pedestrian traffic, and/or the like.

The object detection system 900 may therefore analyze images captured bythe imaging sensor(s) 902 to identify one or more dynamic objects, forexample, vehicles, people, bicycles and/or the like in the intersection1100. The boxed dynamic objects may therefore indicate detected, trackedand/or monitored objects.

However, in order to effectively detect, tracked and/or monitor thedynamic objects and compute their location, position and/or the like theimaging senor(s) 902 need to be accurately calibrated. Moreover, inorder to efficiently monitor the traffic (either vehicular or human),the object detection system 900 may need to detect the dynamic objectswith respect to one or more infrastructure elements of the intersection1100, for example, separator lanes, pedestrian crossings, vehicle stoplines, entry points of the intersection 100, exit points of theintersection 100 and/or the like.

To this end, one or more reference markings may be painted in theintersection 1100 as seen in FIG. 11B.

For example, calibration reference markings 1102 may be painted on theroad surface across the intersection 1100. Moreover, a plurality ofcalibration points 1104 may be painted on the sidewalk surface and/orthe road surface at key points of the intersection 1100, for example, atthe four corners of the intersection 1100, in the middle of theintersection 1100 and/or the like. One or more imaging sensors 902deployed at the intersection 1100 may capture one or more images of theintersection 1100, specifically in one or more of the infrared spectralranges. The captured image(s) may be analyzed to identify one or more ofthe calibration reference markings 1102 and/or 1104 and their position.The respective imaging sensor 902 which captured the image(s) may bethen calibrated according to the position, location and/or orientationof the identified calibration reference markings 1102 and/or 1104.

In another example, one or more reference markings 1106 may be paintedon the road surface at each entry point and/or exit point of theintersection 1100. One or more traffic monitoring systems, for example,a red-light crossing detection system may use the reference markings1106 to accurately identify the entry and exit points of theintersection 1100 and thus accurately detect vehicles that cross anentry point and/or an exit point during red light.

In another example, one or more reference markings 1108 may be paintedon the road surface at stop lines of motorized vehicles lanes of theintersection 1100. Moreover, one or more reference markings 1110 may bepainted on the road surface at stop lines of bicycle lanesentering/exiting the intersection 1100. One or more traffic monitoringsystems, for example, the red-light crossing detection system mayfurther use the reference markings 1108 and/or 1110 to accuratelyidentify the stop lines and further accurately detect vehicles and/orbicycles that cross these stop lines during red light.

In another example, one or more reference markings 1112 may be paintedon the road surface over lane separator lines of lanes going in and outof the intersection 1100. One or more traffic monitoring systems, forexample, an accident analysis system may further use the referencemarkings 1112 to accurately identify the lane separators and inparticular, detect position, location, speed and/or the like of one ormore vehicles, bicycles and/or pedestrians with respect to laneseparator lines.

The descriptions of the various embodiments of the present inventionhave been presented for purposes of illustration, but are not intendedto be exhaustive or limited to the embodiments disclosed. Manymodifications and variations will be apparent to those of ordinary skillin the art without departing from the scope and spirit of the describedembodiments. The terminology used herein was chosen to best explain theprinciples of the embodiments, the practical application or technicalimprovement over technologies found in the marketplace, or to enableothers of ordinary skill in the art to understand the embodimentsdisclosed herein.

It is expected that during the life of a patent maturing from thisapplication many relevant systems, methods and computer programs will bedeveloped and the scope of the terms infrared reflective, absorptiveand/or at least partially infrared - transparent paint materials andimaging sensor are intended to include all such new technologies apriori.

As used herein the term “about” refers to ±10%.

The terms “comprises”, “comprising”, “includes”, “including”, “having”and their conjugates mean “including but not limited to”. This termencompasses the terms “consisting of” and “consisting essentially of”.

The phrase “consisting essentially of” means that the composition ormethod may include additional ingredients and/or steps, but only if theadditional ingredients and/or steps do not materially alter the basicand novel characteristics of the claimed composition or method.

As used herein, the singular form “a”, “an” and “the” include pluralreferences unless the context clearly dictates otherwise. For example,the term “a compound” or “at least one compound” may include a pluralityof compounds, including mixtures thereof.

The word “exemplary” is used herein to mean “serving as an example, aninstance or an illustration”. Any embodiment described as “exemplary” isnot necessarily to be construed as preferred or advantageous over otherembodiments and/or to exclude the incorporation of features from otherembodiments.

The word “optionally” is used herein to mean “is provided in someembodiments and not provided in other embodiments”. Any particularembodiment of the invention may include a plurality of “optional”features unless such features conflict.

Throughout this application, various embodiments of this invention maybe presented in a range format. It should be understood that thedescription in range format is merely for convenience and brevity andshould not be construed as an inflexible limitation on the scope of theinvention. Accordingly, the description of a range should be consideredto have specifically disclosed all the possible subranges as well asindividual numerical values within that range. For example, descriptionof a range such as from 1 to 6 should be considered to have specificallydisclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numberswithin that range, for example, 1, 2, 3, 4, 5, and 6. This appliesregardless of the breadth of the range.

Whenever a numerical range is indicated herein, it is meant to includeany cited numeral (fractional or integral) within the indicated range.The phrases “ranging/ranges between” a first indicate number and asecond indicate number and “ranging/ranges from” a first indicate number“to” a second indicate number are used herein interchangeably and aremeant to include the first and second indicated numbers and all thefractional and integral numerals there between.

The word “exemplary” is used herein to mean “serving as an example, aninstance or an illustration”. Any embodiment described as “exemplary” isnot necessarily to be construed as preferred or advantageous over otherembodiments and/or to exclude the incorporation of features from otherembodiments.

The word “optionally” is used herein to mean “is provided in someembodiments and not provided in other embodiments”. Any particularembodiment of the invention may include a plurality of “optional”features unless such features conflict.

It is appreciated that certain features of the invention, which are, forclarity, described in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures of the invention, which are, for brevity, described in thecontext of a single embodiment, may also be provided separately or inany suitable sub-combination or as suitable in any other describedembodiment of the invention. Certain features described in the contextof various embodiments are not to be considered essential features ofthose embodiments, unless the embodiment is inoperative without thoseelements.

Although the invention has been described in conjunction with specificembodiments thereof, it is evident that many alternatives, modificationsand variations will be apparent to those skilled in the art.Accordingly, it is intended to embrace all such alternatives,modifications and variations that fall within the spirit and broad scopeof the appended claims.

It is the intent of the applicant(s) that all publications, patents andpatent applications referred to in this specification are to beincorporated in their entirety by reference into the specification, asif each individual publication, patent or patent application wasspecifically and individually noted when referenced that it is to beincorporated herein by reference. In addition, citation oridentification of any reference in this application shall not beconstrued as an admission that such reference is available as prior artto the present invention. To the extent that section headings are used,they should not be construed as necessarily limiting. In addition, anypriority document(s) of this application is/are hereby incorporatedherein by reference in its/their entirety.

What is claimed is:
 1. A method of detecting dynamic objects using roadpainted patterns perceptible in infrared spectral range, comprising:using at least one processor for: receiving at least one infrared imagedepicting, in at least one infrared spectral range, at least one surfaceof at least one road segment painted with at least one backgroundpattern using at least one paint material characterized by: (1)reflecting light in visible light spectral range deviating less than afirst value from the light reflected by the at least one surface, and(2) reflecting light in the at least one infrared spectral rangedeviating more than a second value from the light reflected by the atleast one surface; analyzing the at least one infrared image todetecting at least one dynamic object located in front of the at leastone background pattern, the light reflected by the at least one dynamicobject in the infrared spectral range deviating from the light reflectedby the at least one background pattern; and computing a location of theat least one identified object.
 2. The method of claim 1, wherein the atleast one dynamic object is a member of a group consisting of: a vehicleand a pedestrian.
 3. The method of claim 1, wherein the first valueequals 20% and the second value equals 25%.
 4. The method of claim 1,wherein the at least one infrared spectral range is a member of a groupconsisting of: near infrared (NIR) having a wavelength in a range of750-1400 nanometer, and short wave infrared (SWIR) having a wavelengthin a range of 1400-3000 nanometer.
 5. The method of claim 1, furthercomprising a plurality of background patterns are painted on the atleast one surface suing a plurality of paint material such as the atleast one paint material which are further characterized by reflectinglight in the at least one infrared spectral range deviating from eachother by more than a third value, the third value equals 25%.
 6. Themethod of claim 1, further comprising the second value of the at leastone paint material characterizes the at least one paint material totransfer more than a fourth value of light in the infrared spectralrange thus exposing the at least one background pattern painted beneaththe at least one paint material, the fourth value equals 85%.
 7. Themethod of claim 1, further comprising analyzing the at least one imageto compute at least one attribute of the at least one identified object,the at least one attribute is a member of a group consisting of: a size,a length, a width, a height, a speed, an acceleration and a movementdirection.
 8. The method of claim 1, wherein the at least one surface onwhich the at least one background pattern is painted comprises at leastone member of a group consisting of: a road surface, a sidewalk surfaceand a transportation infrastructure object surface.
 9. The method ofclaim 1, wherein the at least one background pattern is applied over theat least one surface which is already painted with at least one paintmaterial perceptible in the visible light range.
 10. The method of claim1, wherein the at least one background pattern is painted according toinstructions computed automatically based on at least one image of theat least one road segment.
 11. A background pattern painted on at leastone surface of at least one road segment using at least one paintmaterial characterized by: (1) reflecting light in visible lightspectral range deviating less than a first value from the lightreflected by the at least one surface, and (2) reflecting light in atleast one infrared spectral range deviating more than a second valuefrom the light reflected by the at least one surface; wherein at leastone dynamic object reflecting light in the infrared spectral rangedeviating from the light reflected by the background pattern isdetectable when located in front of the background pattern.
 12. A methodof calibrating imaging sensors deployed to monitor roads trafficaccording to infrared visible reference markings, comprising: using atleast one processor for: receiving at least one at least one infraredimage captured by at least one imaging sensor depicting, in at least oneinfrared spectral range, at least one surface of at least one roadsegment painted with at least one reference markings using at least onepaint material characterized by: (1) reflecting light in visible lightspectral range deviating less than a first value from the lightreflected by the at least one surface, and (2) reflecting light in atleast one infrared spectral range deviating more than a second valuefrom the light reflected by the at least one surface; analyzing the atleast one infrared image to determine a position of the at least onereference markings; and calibrating the at least one imaging sensoraccording to the computed position of the at least one referencemarkings.
 13. The method of claim 12, wherein the at least one referencemarkings further comprising an identifier of the at least one roadsegment.
 14. The method of claim 12, wherein the first value equals 20%and the second value equals 25%.
 15. The method of claim 12, wherein theat least one infrared spectral range is a member of a group consistingof near infrared (NIR) having a wavelength in a range of 750-1400nanometer, and short wave infrared (SWIR) having a wavelength in a rangeof 1400-3000 nanometer.
 16. The method of claim 12, further comprisingthe second value of the at least one paint material characterizes the atleast one paint material to transfer more than a fourth value of lightin the infrared spectral range thus exposing the at least one referencemarkings painted beneath the at least one paint material, the fourthvalue equals 85%.
 17. The method of claim 12, wherein the surface onwhich the at least one reference markings are painted comprises at leastone member of a group consisting of: a road surface, a sidewalk surfaceand a transportation infrastructure object surface.
 18. The method ofclaim 12, wherein the at least one reference markings are applied overthe at least one surface which is already painted with at least onepaint material perceptible in the visible light range.
 19. The method ofclaim 12, wherein the at least one reference markings is paintedaccording to instructions computed automatically based on at least oneimage of the at least one road segment.